NUM, NUMCHECK
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| command | return value | value of RC |
|---|---|---|
NUM expression
|
value of expression or empty string if the evaluation fails |
0 error code |
NUMCHECK expression
|
value of expression or empty string if the evaluation fails |
0 warning code |
- Description
- The expression will be evaluated numerically, and the result (textual representation) will be returned. The expression may consist of the following parts:
- decimal numbers
123.456, 17.5e3, 100, -312.123, 1e-3- hexa-decimal numbers
0x1234, 0xabc, 0XabC- special constants
pi(=3.1415...),e(=2.71828...),rand(a linear distributed pseudo random number r; -1≤r<1)lran(a linear distributed pseudo random number r; 0≤r<1)- numerical operators
-a(negate),a+b(add),a-b(subtract),a*b(multiply),a/b(divide),a%b(modulo),a^b (power)- logical operators (bitwise)
!a(not),a&b(and),a|b(or),a^b(exclusive or)- brackets
(expression)- functions
setlran(seed)linear distributed pseudo random number r (0≤r<1)
seed is the start value (0≤seed<<1)sin(x), cos(x), tan(x)sine, cosine or tangent of x asin(x), acos(x), atan(x)inverse sine, cosine or tangent of x exp(x)computes exlog(x)common logarithm of x (base 10)ln(x)natural logarithm of x (base e)sqrt(x)square root of x (base 10) abs(x)absolute value of x (base 10) int(x)integer part of x, the fractional part is truncated
(range of x: 32bit signed integer)round(x)round to the nearest integer of x
(range of x: 32bit signed integer)db(x)convert level to factor ( 10x/20)sinc(x), sinx(x)sinc function: sin(x) / xsign(x)sign of x; returns -1 if x<0, otherwise 1hz2bark(x)convert x from Hertz to Bark bark2hz(x)convert x from Bark to Hertz bit(n)returns the integer with only bit n (0≤n<32) is set and all other are cleared; can be used to generate bit masks floor(x)returns a floating-point value representing the largest integer that is less than or equal to x
(range of x: 64bit float)iserr(rc), iserror(rc)returns 1 if rc is a STx error code, otherwise 0
this function can be used to test the completion codeRCof a commandiswarn(rc), iswarning(rc)returns 1 if rc is a STx warning code, otherwise 0
this function can be used to test the completion codeRCof a commandnpow2(n)next power of 2; returns the smallest possible value 2m ≥ n
- Notes
-
- In case of the expression being syntactically ill-formed, an error (
INT) or warning (INTCHECK) is reported. - The same expression syntax is used for the INT and INTCHECK command and for the numerical expressions in conditions (e.g. IF or WHILE).
- In case of the expression being syntactically ill-formed, an error (
- Notes
-
- The
INTcommand converts the result to an integer by truncating it. There is no rounding involved, no rounding at all.
- The
- See also
- NUM, NUMCHECK, EVAL, EVALCHECK
- Examples
#result := int 3.1 // #result is set to 3
#result := int 3.9 // #result is set to 3, too
#result := int 3.9 * 3.9 // #result is set to 15 (note that calculation
// is done in floating point, resulting in 15.21,
// and truncation occurs only on assigning
// compare the preceding example with the following one:
#result := int 3 * int(3.9) // here, #result will be assigned 9 - cool, isn't it?