Library with various static methods for typical but generic business logic like measurement unit conversions, calculations, date and time parsing, data sanitizing and manipulation, textual formatting, etc.
The subfolder tests in the folder extras, i.e., gbj_apphelpers/extras/test, contains testing files, usually just one, with unit tests of library gbj_apphelpers executable by Unity test runner. Each testing file should be placed in an individual test subfolder of a particular project, usually in the structure test/test_<testname>/<testfile>.
The name of a test subfolder should be prefixed with
test_otherwise the test is ignored, e.g.,test_mytest.
- calculate_digits.cpp: Test suite providing test cases for determining count of digits in non-negative integers.
- parse_datetime.cpp: Test suite providing test cases for datatime strings and structure parsing.
- sanitize.cpp: Test suite providing test cases for sanitizing data values with default ones of various data types for valid range.
- sort_data.cpp: Test suite providing test cases for sorting with method buble sorting.
- swap_data.cpp: Test suite providing test cases for swapping a pair of data items.
- temperature_conversion.cpp: Test suite providing test cases for temperature conversion between Celsius, Farenheit, and Kelvin scales.
- format_seconds.cpp: Test suite providing test cases for formatting time periods.
The class is not intended to be instantiated. Each method can be called directly as qualified method name, i.e., just with concatenation of the class name scope resolution operator, and method name. For example:
#include "gbj_apphelpers.h"
float tempF = gbj_apphelpers::convertCelsius2Fahrenheit(20.0)- calculateDewpoint()
- calculateDigits()
- calculateAltitudeFromPressures()
- calculatePressureSeaFromAltitude()
Custom data type defining the structure of date and time parameters for setting and reading datetime usually to and from real time clock chips.
using Datetime = struct Datatime
{
uint16_t year;
uint8_t month;
uint8_t day;
uint8_t hour;
uint8_t minute;
uint8_t second;
uint8_t weekday;
bool mode12h;
bool pm;
}
-
year: Number of a year counting from zero. For setting date only last 2 digits are relevant, that are written to an RTC chip. Corresponding methods reading from RTC chips usually expect 21st century and add 2000 to read two-digit year.
- Valid values: 0 ~ 99
- Default value: 0
-
month: Number of a month in a year counting from 1 for January.
- Valid values: 1 ~ 12
- Default value: 1
-
day: Number of a day in a month.
- Valid values: 1 ~ 31
- Default value: 1
-
hour: Number of an hour in a day.
- Valid values: 0 ~ 23 for 24 hours mode, 1 ~ 12 for 12 hours mode
- Default value: 0
-
minute: Number of a minute in an hour.
- Valid values: 0 ~ 59
- Default value: 0
-
second: Number of a second in a minute.
- Valid values: 0 ~ 59
- Default value: 0
-
weekday: Number of a day in a week. It is up to an application to set the starting day of a week. Usually the first day is Sunday or Monday.
- Valid values: 1 ~ 7
- Default value: 1
-
mode12h: Flag about using 12 hours mode.
- Valid values: Boolean; true for 12 hours mode, false for 24 hours one
- Default value: false
-
pm: Flag about past meridiem. It is relevant for 12 hours mode only but is set correctly at reading from an RTC chip at 24 hours mode as well.
- Valid values: Boolean; true for PM, false for AM
- Default value: false
The method calculates dew point temperature from provided ambient relative humidity and temperature.
uint8_t calculateDewpoint(float rhum, float temp)
-
rhum: Ambient relative humidity in per cent.
- Valid values: rational numbers greater than 0.0
- Default value: none
-
temp: Ambient temperature in centigrade.
- Valid values: rational numbers greater than -273.15 but other than -235.66
- Default value: none
Dew point temperature in centigrade or the error value -999.0.
The method determines count of digits in an integer number expressed in decimal notation, while zero number is counted as 1 digit.
uint8_t calculateDigits(uint32_t number)
- number: Tested non-negative integer.
- Valid values: 0 - (2^32 - 1)
- Default value: none
Number of digits in the integer at decimal notation in range 0 ~ 10.
The method calculates local altitude from provided local barometric pressure and corresponding sea level pressure. - Both input pressures should be in the same measurement unit. However that unit can be arbitrary, usually Pascal or hectoPascal.
float calculateAltitudeFromPressures(float pressure, float pressureSea)
-
pressure: Local barometric pressure in arbitrary measurement unit, usually Pascal or hectoPascal.
- Valid values: decimal number
- Default value: none
-
pressureSea: Sea level barometric pressure in arbitrary measurement unit, but the same as the first argument has.
- Valid values: decimal number
- Default value: none
Altitude in meters.
The method calculates barometric pressure at sea level from provided local pressure and altitude.
- The measurement unit of the local pressure can be arbitrary. However the methods returns the sea level pressure in the same unit.
float calculatePressureSeaFromAltitude(float pressure, float altitude)
-
pressure: Local barometric pressure in arbitrary measurement unit, usually Pascal or hectoPascal.
- Valid values: decimal number
- Default value: none
-
altitude: Local altitude in meters for which the equivalent sea level pressure should be calculated.
- Valid values: decimal number
- Default value: none
Sea level barometric pressure.
The particular method calculates temperature expressed in one temperature scale to another one as indicates its name.
float convertCelsius2Fahrenheit(float temp)
float convertFahrenheit2Celsius(float temp)
- temp: Temperature in measurement units of source temperature scale.
- Valid values: rational numbers
- Default value: none
Temperature in measurement units of target temperature scale.
The method reads a GPIO pin until the read value is same as input value.
- The method is considered as a software button debouncing.
uint8_t debounce(uint8_t iniVal, uint8_t pin)
-
iniVal: Initially read a pin value.
- Valid values: 0 - 255
- Default value: none
-
pin: GPIO number of a microcontroller with connected button.
- Valid values: 0 - 255
- Default value: none
Steady input value of the pin.
The method extracts corresponding parts of a date as well as time structure from strings formatted as a compiler DATE and TIME system constants, e.g., Dec 26 2018 and 12:34:56.
- The method is overloaded, either for flashed constants or for generic strings in SRAM.
- The method does not update Datetime members
weekday,mode12h, andpm.
void parseDateTime(Datetime &dtRecord, const char* strDate, const char* strTime)
void parseDateTime(Datetime &dtRecord, const __FlashStringHelper* strDate, const __FlashStringHelper* strTime)
-
dtRecord: Referenced structure variable for desired date and time.
- Valid values: Datetime
- Default value: none
-
strDate: Pointer to a system date formatted string.
- Valid values: address space
- Default value: none
-
strTime: Pointer to a system time formatted string.
- Valid values: address space
- Default value: none
None. Indirectly updated referenced variable for datetime structure.
gbj_apphelpers::Datetime rtcDateTime;
gbj_apphelpers::parseDateTime(rtcDateTime, __DATE__, __TIME__);
gbj_apphelpers::parseDateTime(rtcDateTime, F(__DATE__), F(__TIME__));The method tests input value for valid range defined by minimum and maximum value.
- Values can be of any comparable data type, but all of the same one.
template<class T>
bool check(T valCur, T valMin, T valMax)
- valCur: Input tested current value.
- valMin: Minimal value of a valid range (value space).
- valMax: Maximal value of a valid range (value space).
Boolean flag about current value inside the valid range.
The method tests input value for valid range defined by minimum and maximum value. If it is outside of the range, method replaces input value with default value.
- Values can be of any comparable data type, but all of the same one.
template<class T>
T sanitize(T valCur, T valDft, T valMin, T valMax)
- valCur: Input tested current value.
- valDft: Default value used instead input value for the result.
- valMin: Minimal value of a valid range (value space).
- valMax: Maximal value of a valid range (value space).
- Input current value if it is inside the valid range.
- Default value if input current value is outside the valid range.
Corresponding method sorts data items in a provided referenced buffer with help of buble sorting algorithm.
- Values in data buffer can of any comparable data type.
template <class T>
void sort_buble_asc(T *dataBuffer, uint16_t dataLen)
void sort_buble_desc(T *dataBuffer, uint16_t dataLen)
-
dataBuffer: Referenced data buffer with data items of various data type.
- Valid values: for used data type
- Default value: none
-
dataLen: Number of the first data items in the buffer to sort.
- Valid values: 0 ~ 65535
- Default value: none
None. Indirectly sorted referenced data buffer.
The method swappes input data items pair upside down.
- Values can be of any data type, but all of the same one.
template<class T>
void swapdata(T &item1, T &item2)
- item1, item2: Referenced data items to be swapped.
- Valid values: for used data type
- Default value: none
None. Indirectly swapped values of referenced variables.
The method formats input seconds since midnight to string with hours, minutes, and seconds all with leading zeros.
- Formatted output is of form
??:??:??.
String formatTimeDay(uint32_t totalSeconds)
- totalSeconds: Number of seconds since midnight in a day.
- Valid values: 32-bit unsigned integer
- Default value: none
Formatted string as an expression of a time within a day.
The method formats input time period in seconds to string with days, hours, minutes, and seconds with leading spaces.
- Formatted output is of form
???d ??h ??m ??s. - Leading zero segments are omitted from output, e.g., for time period shorter than one hour and equal or longer than one minute it is
??m ??s.
String formatTimePeriod(uint32_t totalSeconds)
- totalSeconds: Time period in seconds.
- Valid values: 32-bit unsigned integer
- Default value: none
Formatted string as an expression of a time period at most in days.
The method formats input time period in seconds to string with days, hours, minutes, and seconds without any spaces.
- Formatted output is of form
???d??h??m??s. - Leading zero segments are omitted from output, e.g., for time period shorter than one hour and equal or longer than one minute it is
??m??s.
String formatTimePeriodDense(uint32_t totalSeconds)
- totalSeconds: Time period in seconds.
- Valid values: 32-bit unsigned integer
- Default value: none
Formatted string as an expression of a time period at most in days without delimiting spaces.