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Function | Bounds-checking |
|---|---|
acos(x) | -1 <= x && x <= 1 |
atan2 | x != 0 || y != 0 |
log, log10 | x >= 0 |
pow(x, y) | x != 0 || y > 0 |
sqrt(x) | x >= 0 |
The calling function should take alternative action if these bounds are violated.
acos
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, asin
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Non-Compliant Code Example
| Wiki Markup |
|---|
The followingThis code may produce a domain error if the argument is not in the range \[-1, \+1\]. |
| Code Block |
|---|
float x, result; result = acos(x); |
Compliant
...
Solution
The following This code uses bounds checking to ensure there is not a domain error.
| Code Block |
|---|
float x, result;
if( islessequal(x,-1) || isgreaterequal(x, 1) ){
/* handle domain error */
}
result = acos(x);
|
atan2(y, x)
Non-Compliant
...
Code Example
The following This code may produce a domain error if both x and y are zero.
| Code Block |
|---|
float x, y, result; result = atan2(y, x); |
Compliant Solution
The following This code tests the arguments to ensure that there is not a domain error.
| Code Block |
|---|
float x, y, result;
if( fpclassify(x) == FP_ZERO && fpclassify(y) == FP_ZERO){
/* handle domain error */
}
result = atan2(y, x);
|
log
...
, log10
...
Non-Compliant Code Example
The following This code may produce a domain error if x is negative and a range error if x is zero.
| Code Block |
|---|
float result, x; result = log(x); |
Compliant
...
Solution
The following This code tests the suspect arguments to ensure no domain or range errors are raised.
| Code Block |
|---|
float result, x;
if(islessequal(x, 0)){
/* handle domain and range errors */
}
result = log(x);
|
pow(x,y)
Non-Compliant Code Example
The following This code may produce a domain error if x is zero and y less than or equal to zero. A range error may also occur if x is zero and y is negative.
| Code Block |
|---|
float x, y, result; result = pow(x,y); |
Compliant Solution
The following This code tests x and y to ensure that there will be no range or domain errors.
| Code Block |
|---|
float x, y, result;
if(fpclassify(x) == FP_ZERO && islessequal(y, 0)){
/* handle domain error condition */
}
result = pow(x, y);
|
sqrt
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Non-Compliant
...
Code Example
The following This code may produce a domain error if x is negative.
| Code Block |
|---|
float x, result; result = sqrt(x); |
Compliant Solution
The following This code tests the suspect argument to ensure no domain error is raised.
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