jupyterpidaq.Boards.Simulated.ADCsim_line
1# Noisy line substitute for actual analog to digital converter. 2# Used to allow a 'demo' mode for JupyterPiDAQ. 3# J. Gutow <jgutow@new.rr.com> June 11, 2020 4# license GPL V3 or greater 5 6import time 7 8from numpy import around 9from numpy import float64 10from numpy import floor 11from numpy import log10 12from numpy import random 13from numpy import sqrt 14from numpy import std 15 16from jupyterpidaq.Boards import Board 17 18# mimicking an installed ADS1115 ADC PiHAT. 19RATE = 475 20# 475 Hz with oversampling best S/N on Pi 3B+ per unit time interval. 21 22 23# other rates 8, 16, 32, 64, 128, 250, 475, 860 in Hz. 24def find_boards(): 25 return Board_ADCsim_line('placeholder') 26 27 28class Board_ADCsim_line(Board): 29 """ 30 This class simulates an Analog-to-Digital board that returns a linearly 31 increasing signal with a small amount of noise on the signal. The 32 intercept and slope depend upon which hour of the day the simulation is 33 run. 34 """ 35 def __init__(self, adc): 36 super().__init__() 37 self.name = 'ADCsym Line' 38 self.vendor = 'JupyterPiDAQ' 39 self.channels = (0, 1, 2, 3) 40 self.gains = [1] 41 self.Vdd = 3.3 42 self.adc = adc 43 44 def getsensors(self): 45 """ 46 Return a list of valid sensor object names for this board. 47 :return: list of classnames 48 """ 49 sensorlist = ['RawAtoD', 50 'VernierSSTemp', 51 'VernierGasP', 52 'VernierpH', 53 'VernierFlatpH' 54 ] 55 # TODO: extend this list as appropriate. You can get a full list 56 # using the `Sensors.sensors.listSensors()` call. 57 # The main program will use this list to access the actual sensor 58 # objects when converting the raw board voltage and for producing 59 # a menu of valid options for this particular board. 60 return sensorlist 61 62 def V_oversampchan(self, chan, gain, avg_sec, data_rate=RATE): 63 """ 64 This routine returns the average voltage for the channel 65 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 66 number of seconds. The 0.0012 is the required loop time 67 on a RPI 3B+ in python3. The voltage is rounded to the number 68 of decimals indicated by the standard deviation. The standard 69 deviation and the estimated deviation of the mean are also 70 returned. 71 Parameters 72 chan the channel number 0, 1, 2, 3 73 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 74 8 (+/-0.512V), 16 (+/-0.256V) 75 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 76 or 860 Hz) 77 avg_sec seconds to average for, actual averaging interval will be 78 as close as possible for an integer number of samples. 79 Returns a tuple (V_avg, V_min, V_max, time_stamp) 80 V_avg the averaged voltage 81 stdev estimated standard deviation of the measurements 82 stdev_avg estimated standard deviation of the mean 83 time_stamp the time at halfway through the averaging interval in 84 seconds since the beginning of the epoch (OS dependent begin 85 time). 86 87 """ 88 time_tuple = time.localtime() 89 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 90 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 91 time_tuple.tm_wday, time_tuple.tm_yday, 92 time_tuple.tm_isdst)) 93 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 94 if n_samp < 1: 95 n_samp = 1 96 value = [] 97 start = time.time() 98 intercept = (time.time() - nearesthr) / 1800 99 slope = (time.time() - nearesthr) / 692000 100 for k in range(n_samp): 101 tempval = intercept + slope * (time.time() - nearesthr) + ( 102 random.random() - 0.5) * slope 103 value.append(tempval) 104 end = time.time() 105 time_stamp = (start + end) / 2.0 106 V_avg = sum(value) / len(value) / gain 107 V_max = max(value) 108 V_min = min(value) 109 return V_avg, V_min, V_max, time_stamp, self.Vdd 110 111 def V_oversampchan_stats(self, chan, gain, avg_sec, data_rate=RATE): 112 """ 113 This routine returns the average voltage for the channel 114 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 115 number of seconds. The 0.0012 is the required loop time 116 on a RPI 3B+ in python3. The voltage is rounded to the number 117 of decimals indicated by the standard deviation. The standard 118 deviation and the estimated deviation of the mean are also 119 returned. 120 Parameters 121 chan the channel number 0, 1, 2, 3 122 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 123 8 (+/-0.512V), 16 (+/-0.256V) 124 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 125 or 860 Hz) 126 avg_sec seconds to average for, actual averaging interval will be 127 as close as possible for an integer number of samples. 128 Returns a tuple (V_avg, V_min, V_max, time_stamp) 129 V_avg the averaged voltage 130 stdev estimated standard deviation of the measurements 131 stdev_avg estimated standard deviation of the mean 132 time_stamp the time at halfway through the averaging interval in 133 seconds since the beginning of the epoch (OS dependent begin 134 time). 135 136 """ 137 time_tuple = time.localtime() 138 currhr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 139 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 140 time_tuple.tm_wday, time_tuple.tm_yday, 141 time_tuple.tm_isdst)) 142 currdy = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 143 time_tuple.tm_mday, 0, 0, 0, 144 time_tuple.tm_wday, time_tuple.tm_yday, 145 time_tuple.tm_isdst)) 146 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 147 if n_samp < 1: 148 n_samp = 1 149 value = [] 150 start = time.time() 151 intercept = (currhr - currdy) / 24 / 3600 - 0.5 152 slope = (currhr - currdy) / 24 / 3600 / 300 153 for k in range(n_samp): 154 tempval = intercept + slope * (time.time() - currhr) + ( 155 random.random() - 0.5) * slope 156 value.append(tempval) 157 end = time.time() 158 time_stamp = (start + end) / 2 159 V_avg = sum(value) / len(value) / gain 160 stdev = std(value, ddof=1, dtype=float64) / gain 161 stdev_avg = stdev / sqrt(float(len(value))) 162 decimals = 0 163 if stdev_avg == 0: 164 decimals = 6 165 else: 166 if (stdev_avg != float('inf')) and (stdev_avg > 0): 167 decimals = -int(floor(log10(stdev_avg))) 168 # print('decimals = '+str(decimals)) 169 V_avg = around(V_avg, decimals=decimals) 170 stdev = around(stdev, decimals=decimals) 171 stdev_avg = around(stdev_avg, decimals=decimals) 172 return V_avg, stdev, stdev_avg, time_stamp, self.Vdd 173 174 def V_sampchan(self, chan, gain, data_rate=RATE): 175 """ 176 This routine returns the average voltage for the channel 177 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 178 number of seconds. The 0.0012 is the required loop time 179 on a RPI 3B+ in python3. The voltage is rounded to the number 180 of decimals indicated by the standard deviation. The standard 181 deviation and the estimated deviation of the mean are also 182 returned. 183 Parameters 184 chan the channel number 0, 1, 2, 3 185 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 186 8 (+/-0.512V), 16 (+/-0.256V) 187 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 188 or 860 Hz) avg_sec seconds to average for, actual averaging 189 interval will be as close as possible for an integer number of 190 samples. 191 Returns a tuple (V_avg, V_min, V_max, time_stamp) 192 V_avg the averaged voltage 193 stdev estimated standard deviation of the measurements 194 stdev_avg estimated standard deviation of the mean 195 time_stamp the time at halfway through the averaging interval in 196 seconds since the beginning of the epoch (OS dependent begin 197 time). 198 199 """ 200 time_tuple = time.localtime() 201 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 202 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 203 time_tuple.tm_wday, time_tuple.tm_yday, 204 time_tuple.tm_isdst)) 205 start = time.time() 206 intercept = (time.time() - nearesthr) / 1800 207 slope = (time.time() - nearesthr) / 692000 208 V = intercept + slope * (time.time() - nearesthr) + (random.random() 209 - 0.5) * slope 210 end = time.time() 211 time_stamp = (start + end) / 2.0 212 return V, time_stamp, self.Vdd
def
find_boards():
29class Board_ADCsim_line(Board): 30 """ 31 This class simulates an Analog-to-Digital board that returns a linearly 32 increasing signal with a small amount of noise on the signal. The 33 intercept and slope depend upon which hour of the day the simulation is 34 run. 35 """ 36 def __init__(self, adc): 37 super().__init__() 38 self.name = 'ADCsym Line' 39 self.vendor = 'JupyterPiDAQ' 40 self.channels = (0, 1, 2, 3) 41 self.gains = [1] 42 self.Vdd = 3.3 43 self.adc = adc 44 45 def getsensors(self): 46 """ 47 Return a list of valid sensor object names for this board. 48 :return: list of classnames 49 """ 50 sensorlist = ['RawAtoD', 51 'VernierSSTemp', 52 'VernierGasP', 53 'VernierpH', 54 'VernierFlatpH' 55 ] 56 # TODO: extend this list as appropriate. You can get a full list 57 # using the `Sensors.sensors.listSensors()` call. 58 # The main program will use this list to access the actual sensor 59 # objects when converting the raw board voltage and for producing 60 # a menu of valid options for this particular board. 61 return sensorlist 62 63 def V_oversampchan(self, chan, gain, avg_sec, data_rate=RATE): 64 """ 65 This routine returns the average voltage for the channel 66 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 67 number of seconds. The 0.0012 is the required loop time 68 on a RPI 3B+ in python3. The voltage is rounded to the number 69 of decimals indicated by the standard deviation. The standard 70 deviation and the estimated deviation of the mean are also 71 returned. 72 Parameters 73 chan the channel number 0, 1, 2, 3 74 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 75 8 (+/-0.512V), 16 (+/-0.256V) 76 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 77 or 860 Hz) 78 avg_sec seconds to average for, actual averaging interval will be 79 as close as possible for an integer number of samples. 80 Returns a tuple (V_avg, V_min, V_max, time_stamp) 81 V_avg the averaged voltage 82 stdev estimated standard deviation of the measurements 83 stdev_avg estimated standard deviation of the mean 84 time_stamp the time at halfway through the averaging interval in 85 seconds since the beginning of the epoch (OS dependent begin 86 time). 87 88 """ 89 time_tuple = time.localtime() 90 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 91 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 92 time_tuple.tm_wday, time_tuple.tm_yday, 93 time_tuple.tm_isdst)) 94 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 95 if n_samp < 1: 96 n_samp = 1 97 value = [] 98 start = time.time() 99 intercept = (time.time() - nearesthr) / 1800 100 slope = (time.time() - nearesthr) / 692000 101 for k in range(n_samp): 102 tempval = intercept + slope * (time.time() - nearesthr) + ( 103 random.random() - 0.5) * slope 104 value.append(tempval) 105 end = time.time() 106 time_stamp = (start + end) / 2.0 107 V_avg = sum(value) / len(value) / gain 108 V_max = max(value) 109 V_min = min(value) 110 return V_avg, V_min, V_max, time_stamp, self.Vdd 111 112 def V_oversampchan_stats(self, chan, gain, avg_sec, data_rate=RATE): 113 """ 114 This routine returns the average voltage for the channel 115 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 116 number of seconds. The 0.0012 is the required loop time 117 on a RPI 3B+ in python3. The voltage is rounded to the number 118 of decimals indicated by the standard deviation. The standard 119 deviation and the estimated deviation of the mean are also 120 returned. 121 Parameters 122 chan the channel number 0, 1, 2, 3 123 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 124 8 (+/-0.512V), 16 (+/-0.256V) 125 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 126 or 860 Hz) 127 avg_sec seconds to average for, actual averaging interval will be 128 as close as possible for an integer number of samples. 129 Returns a tuple (V_avg, V_min, V_max, time_stamp) 130 V_avg the averaged voltage 131 stdev estimated standard deviation of the measurements 132 stdev_avg estimated standard deviation of the mean 133 time_stamp the time at halfway through the averaging interval in 134 seconds since the beginning of the epoch (OS dependent begin 135 time). 136 137 """ 138 time_tuple = time.localtime() 139 currhr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 140 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 141 time_tuple.tm_wday, time_tuple.tm_yday, 142 time_tuple.tm_isdst)) 143 currdy = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 144 time_tuple.tm_mday, 0, 0, 0, 145 time_tuple.tm_wday, time_tuple.tm_yday, 146 time_tuple.tm_isdst)) 147 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 148 if n_samp < 1: 149 n_samp = 1 150 value = [] 151 start = time.time() 152 intercept = (currhr - currdy) / 24 / 3600 - 0.5 153 slope = (currhr - currdy) / 24 / 3600 / 300 154 for k in range(n_samp): 155 tempval = intercept + slope * (time.time() - currhr) + ( 156 random.random() - 0.5) * slope 157 value.append(tempval) 158 end = time.time() 159 time_stamp = (start + end) / 2 160 V_avg = sum(value) / len(value) / gain 161 stdev = std(value, ddof=1, dtype=float64) / gain 162 stdev_avg = stdev / sqrt(float(len(value))) 163 decimals = 0 164 if stdev_avg == 0: 165 decimals = 6 166 else: 167 if (stdev_avg != float('inf')) and (stdev_avg > 0): 168 decimals = -int(floor(log10(stdev_avg))) 169 # print('decimals = '+str(decimals)) 170 V_avg = around(V_avg, decimals=decimals) 171 stdev = around(stdev, decimals=decimals) 172 stdev_avg = around(stdev_avg, decimals=decimals) 173 return V_avg, stdev, stdev_avg, time_stamp, self.Vdd 174 175 def V_sampchan(self, chan, gain, data_rate=RATE): 176 """ 177 This routine returns the average voltage for the channel 178 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 179 number of seconds. The 0.0012 is the required loop time 180 on a RPI 3B+ in python3. The voltage is rounded to the number 181 of decimals indicated by the standard deviation. The standard 182 deviation and the estimated deviation of the mean are also 183 returned. 184 Parameters 185 chan the channel number 0, 1, 2, 3 186 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 187 8 (+/-0.512V), 16 (+/-0.256V) 188 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 189 or 860 Hz) avg_sec seconds to average for, actual averaging 190 interval will be as close as possible for an integer number of 191 samples. 192 Returns a tuple (V_avg, V_min, V_max, time_stamp) 193 V_avg the averaged voltage 194 stdev estimated standard deviation of the measurements 195 stdev_avg estimated standard deviation of the mean 196 time_stamp the time at halfway through the averaging interval in 197 seconds since the beginning of the epoch (OS dependent begin 198 time). 199 200 """ 201 time_tuple = time.localtime() 202 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 203 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 204 time_tuple.tm_wday, time_tuple.tm_yday, 205 time_tuple.tm_isdst)) 206 start = time.time() 207 intercept = (time.time() - nearesthr) / 1800 208 slope = (time.time() - nearesthr) / 692000 209 V = intercept + slope * (time.time() - nearesthr) + (random.random() 210 - 0.5) * slope 211 end = time.time() 212 time_stamp = (start + end) / 2.0 213 return V, time_stamp, self.Vdd
This class simulates an Analog-to-Digital board that returns a linearly increasing signal with a small amount of noise on the signal. The intercept and slope depend upon which hour of the day the simulation is run.
Board_ADCsim_line(adc)
36 def __init__(self, adc): 37 super().__init__() 38 self.name = 'ADCsym Line' 39 self.vendor = 'JupyterPiDAQ' 40 self.channels = (0, 1, 2, 3) 41 self.gains = [1] 42 self.Vdd = 3.3 43 self.adc = adc
Should be overridden by each board and define at minimum: self.name = 'board name/adc name/type' Short an useful to end user self.vendor = 'Vendor/Manufacturer name` self.channels = tuple of available channel IDs self.gains = list of gains self.Vdd = voltage provided by board to sensors
def
getsensors(self):
45 def getsensors(self): 46 """ 47 Return a list of valid sensor object names for this board. 48 :return: list of classnames 49 """ 50 sensorlist = ['RawAtoD', 51 'VernierSSTemp', 52 'VernierGasP', 53 'VernierpH', 54 'VernierFlatpH' 55 ] 56 # TODO: extend this list as appropriate. You can get a full list 57 # using the `Sensors.sensors.listSensors()` call. 58 # The main program will use this list to access the actual sensor 59 # objects when converting the raw board voltage and for producing 60 # a menu of valid options for this particular board. 61 return sensorlist
Return a list of valid sensor object names for this board.
Returns
list of classnames
def
V_oversampchan(self, chan, gain, avg_sec, data_rate=475):
63 def V_oversampchan(self, chan, gain, avg_sec, data_rate=RATE): 64 """ 65 This routine returns the average voltage for the channel 66 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 67 number of seconds. The 0.0012 is the required loop time 68 on a RPI 3B+ in python3. The voltage is rounded to the number 69 of decimals indicated by the standard deviation. The standard 70 deviation and the estimated deviation of the mean are also 71 returned. 72 Parameters 73 chan the channel number 0, 1, 2, 3 74 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 75 8 (+/-0.512V), 16 (+/-0.256V) 76 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 77 or 860 Hz) 78 avg_sec seconds to average for, actual averaging interval will be 79 as close as possible for an integer number of samples. 80 Returns a tuple (V_avg, V_min, V_max, time_stamp) 81 V_avg the averaged voltage 82 stdev estimated standard deviation of the measurements 83 stdev_avg estimated standard deviation of the mean 84 time_stamp the time at halfway through the averaging interval in 85 seconds since the beginning of the epoch (OS dependent begin 86 time). 87 88 """ 89 time_tuple = time.localtime() 90 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 91 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 92 time_tuple.tm_wday, time_tuple.tm_yday, 93 time_tuple.tm_isdst)) 94 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 95 if n_samp < 1: 96 n_samp = 1 97 value = [] 98 start = time.time() 99 intercept = (time.time() - nearesthr) / 1800 100 slope = (time.time() - nearesthr) / 692000 101 for k in range(n_samp): 102 tempval = intercept + slope * (time.time() - nearesthr) + ( 103 random.random() - 0.5) * slope 104 value.append(tempval) 105 end = time.time() 106 time_stamp = (start + end) / 2.0 107 V_avg = sum(value) / len(value) / gain 108 V_max = max(value) 109 V_min = min(value) 110 return V_avg, V_min, V_max, time_stamp, self.Vdd
This routine returns the average voltage for the channel averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec number of seconds. The 0.0012 is the required loop time on a RPI 3B+ in python3. The voltage is rounded to the number of decimals indicated by the standard deviation. The standard deviation and the estimated deviation of the mean are also returned. Parameters chan the channel number 0, 1, 2, 3 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 8 (+/-0.512V), 16 (+/-0.256V) data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 or 860 Hz) avg_sec seconds to average for, actual averaging interval will be as close as possible for an integer number of samples. Returns a tuple (V_avg, V_min, V_max, time_stamp) V_avg the averaged voltage stdev estimated standard deviation of the measurements stdev_avg estimated standard deviation of the mean time_stamp the time at halfway through the averaging interval in seconds since the beginning of the epoch (OS dependent begin time).
def
V_oversampchan_stats(self, chan, gain, avg_sec, data_rate=475):
112 def V_oversampchan_stats(self, chan, gain, avg_sec, data_rate=RATE): 113 """ 114 This routine returns the average voltage for the channel 115 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 116 number of seconds. The 0.0012 is the required loop time 117 on a RPI 3B+ in python3. The voltage is rounded to the number 118 of decimals indicated by the standard deviation. The standard 119 deviation and the estimated deviation of the mean are also 120 returned. 121 Parameters 122 chan the channel number 0, 1, 2, 3 123 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 124 8 (+/-0.512V), 16 (+/-0.256V) 125 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 126 or 860 Hz) 127 avg_sec seconds to average for, actual averaging interval will be 128 as close as possible for an integer number of samples. 129 Returns a tuple (V_avg, V_min, V_max, time_stamp) 130 V_avg the averaged voltage 131 stdev estimated standard deviation of the measurements 132 stdev_avg estimated standard deviation of the mean 133 time_stamp the time at halfway through the averaging interval in 134 seconds since the beginning of the epoch (OS dependent begin 135 time). 136 137 """ 138 time_tuple = time.localtime() 139 currhr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 140 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 141 time_tuple.tm_wday, time_tuple.tm_yday, 142 time_tuple.tm_isdst)) 143 currdy = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 144 time_tuple.tm_mday, 0, 0, 0, 145 time_tuple.tm_wday, time_tuple.tm_yday, 146 time_tuple.tm_isdst)) 147 n_samp = int(round(avg_sec / (0.0017 + 1 / data_rate))) 148 if n_samp < 1: 149 n_samp = 1 150 value = [] 151 start = time.time() 152 intercept = (currhr - currdy) / 24 / 3600 - 0.5 153 slope = (currhr - currdy) / 24 / 3600 / 300 154 for k in range(n_samp): 155 tempval = intercept + slope * (time.time() - currhr) + ( 156 random.random() - 0.5) * slope 157 value.append(tempval) 158 end = time.time() 159 time_stamp = (start + end) / 2 160 V_avg = sum(value) / len(value) / gain 161 stdev = std(value, ddof=1, dtype=float64) / gain 162 stdev_avg = stdev / sqrt(float(len(value))) 163 decimals = 0 164 if stdev_avg == 0: 165 decimals = 6 166 else: 167 if (stdev_avg != float('inf')) and (stdev_avg > 0): 168 decimals = -int(floor(log10(stdev_avg))) 169 # print('decimals = '+str(decimals)) 170 V_avg = around(V_avg, decimals=decimals) 171 stdev = around(stdev, decimals=decimals) 172 stdev_avg = around(stdev_avg, decimals=decimals) 173 return V_avg, stdev, stdev_avg, time_stamp, self.Vdd
This routine returns the average voltage for the channel averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec number of seconds. The 0.0012 is the required loop time on a RPI 3B+ in python3. The voltage is rounded to the number of decimals indicated by the standard deviation. The standard deviation and the estimated deviation of the mean are also returned. Parameters chan the channel number 0, 1, 2, 3 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 8 (+/-0.512V), 16 (+/-0.256V) data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 or 860 Hz) avg_sec seconds to average for, actual averaging interval will be as close as possible for an integer number of samples. Returns a tuple (V_avg, V_min, V_max, time_stamp) V_avg the averaged voltage stdev estimated standard deviation of the measurements stdev_avg estimated standard deviation of the mean time_stamp the time at halfway through the averaging interval in seconds since the beginning of the epoch (OS dependent begin time).
def
V_sampchan(self, chan, gain, data_rate=475):
175 def V_sampchan(self, chan, gain, data_rate=RATE): 176 """ 177 This routine returns the average voltage for the channel 178 averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec 179 number of seconds. The 0.0012 is the required loop time 180 on a RPI 3B+ in python3. The voltage is rounded to the number 181 of decimals indicated by the standard deviation. The standard 182 deviation and the estimated deviation of the mean are also 183 returned. 184 Parameters 185 chan the channel number 0, 1, 2, 3 186 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 187 8 (+/-0.512V), 16 (+/-0.256V) 188 data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 189 or 860 Hz) avg_sec seconds to average for, actual averaging 190 interval will be as close as possible for an integer number of 191 samples. 192 Returns a tuple (V_avg, V_min, V_max, time_stamp) 193 V_avg the averaged voltage 194 stdev estimated standard deviation of the measurements 195 stdev_avg estimated standard deviation of the mean 196 time_stamp the time at halfway through the averaging interval in 197 seconds since the beginning of the epoch (OS dependent begin 198 time). 199 200 """ 201 time_tuple = time.localtime() 202 nearesthr = time.mktime((time_tuple.tm_year, time_tuple.tm_mon, 203 time_tuple.tm_mday, time_tuple.tm_hour, 0, 0, 204 time_tuple.tm_wday, time_tuple.tm_yday, 205 time_tuple.tm_isdst)) 206 start = time.time() 207 intercept = (time.time() - nearesthr) / 1800 208 slope = (time.time() - nearesthr) / 692000 209 V = intercept + slope * (time.time() - nearesthr) + (random.random() 210 - 0.5) * slope 211 end = time.time() 212 time_stamp = (start + end) / 2.0 213 return V, time_stamp, self.Vdd
This routine returns the average voltage for the channel averaged at (0.0012 + 1/data_rate)^-1 Hz for avg_sec number of seconds. The 0.0012 is the required loop time on a RPI 3B+ in python3. The voltage is rounded to the number of decimals indicated by the standard deviation. The standard deviation and the estimated deviation of the mean are also returned. Parameters chan the channel number 0, 1, 2, 3 gain 2/3 (+/-6.144V), 1(+/-4.096V), 2(+/-2.048V), 4(+/-1.024V), 8 (+/-0.512V), 16 (+/-0.256V) data_rate the ADC sample rate in Hz (8, 16, 32, 64, 128, 250, 475 or 860 Hz) avg_sec seconds to average for, actual averaging interval will be as close as possible for an integer number of samples. Returns a tuple (V_avg, V_min, V_max, time_stamp) V_avg the averaged voltage stdev estimated standard deviation of the measurements stdev_avg estimated standard deviation of the mean time_stamp the time at halfway through the averaging interval in seconds since the beginning of the epoch (OS dependent begin time).