Mathematical Functions
TwinCAT has its own mathematical functions implemented, because the math.h implementation provided by Microsoft is not real-time capable.
These functions are declared in TcMath.h, which is part of TwinCAT SDK. For x64 the operations are executed via SSE; on x86 systems the FPU is used.
 | TwinCAT 3.1 4018 or earlier TwinCAT 3.1 4018 provides an fpu87.h with the same methods. This continues to exist and redirects to TcMath.h. |
Methods provided
Name | Description |
|---|---|
sqr_ | Calculates the square. |
sqrt_ | Calculates the square root. |
sin_ | Calculates the sine. |
cos_ | Calculates the cosine. |
tan_ | Calculates the tangent. |
atan_ | Calculates the angle whose tangent is the specified value. |
atan2_ | Calculates the angle whose tangent is the quotient of two specified values. |
asin_ | Calculates the angle whose sine is the specified value. |
acos_ | Calculates the angle whose cosine is the specified value. |
exp_ | Calculates e to the specified power. |
log_ | Calculates the logarithm of a specified value. |
log10_ | Calculates the base 10 logarithm of a specified value. |
fabs_ | Calculates the absolute value. |
fmod_ | Calculates the remainder. |
ceil_ | Calculates the smallest integer that is greater than or equal to the specified number. |
floor_ | Calculates the largest integer that is smaller than or equal to the specified number. |
pow_ | Calculates a specified number to the specified power. |
sincos_ | Calculates the sine and cosine of x. |
fmodabs_ | Calculates the absolute value that meets the Euclidean definition of the mod operation. |
round_ | Calculates a value and rounds to the nearest integer. |
round_digits_ | Calculates a rounded value with a specified number of decimal places. |
coubic_ | Calculates the cubic value. |
ldexp_ | Calculates a real number (double) from mantissa and exponent. |
ldexpf_ | Calculates a real number (float) from mantissa and exponent. |
sinh_ | Calculates the hyperbolic sine of the specified angle. |
cosh_ | Calculates the hyperbolic cosine of the specified angle. |
tanh_ | Calculates the hyperbolic tangent of the specified angle. |
finite_ | Determines whether the specified value is finite. |
isnan_ | Determines whether the specified value is not a number (NAN). |
rands_ | Calculates a pseudo random number between 0 and 32767. The parameter holdrand is set randomly and changed with every call. |
Comments
The functions have the extension "_" (underscore), which identifies them as TwinCAT implementation.
Most are analog math.h, designed by Microsoft, only for the data type double.