Programmer Guide/Command Reference/NUM: Difference between revisions
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|next power of 2; returns the smallest possible value <code>2<sup>m</sup> ≥ ''n''</code> | |next power of 2; returns the smallest possible value <code>2<sup>m</sup> ≥ ''n''</code> | ||
|} | |} | ||
;Notes: | |||
:*In case of the expression being syntactically ill-formed, an error (<code>INT</code>) or warning (<code>INTCHECK</code>) is reported. | |||
:*The same expression syntax is used for the [[../INT|INT and INTCHECK]] command and for the numerical expressions in [[Programmer_Guide/Introduction#Conditional_Expressions|conditions]] (e.g. [[../IF|IF]] or [[../WHILE|WHILE]]). | |||
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;Notes: | ;Notes: | ||
:* The <code>INT</code> command converts the result to an integer by ''truncating'' it. There is no rounding involved, no rounding at all. | :* The <code>INT</code> command converts the result to an integer by ''truncating'' it. There is no rounding involved, no rounding at all. | ||
;See also: [[../NUM|NUM, NUMCHECK]], [[../EVAL|EVAL, EVALCHECK]] | ;See also: [[../NUM|NUM, NUMCHECK]], [[../EVAL|EVAL, EVALCHECK]] | ||
Revision as of 10:46, 26 April 2011
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 ex
log(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) / x
sign(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 codeRC
of 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 codeRC
of 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
INT
command 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?