LMU/musrfit
5
0
Fork 0
Code Issues 6 Pull Requests Actions Packages Projects Releases 4 Activity

slight improvement to avoid nan's when using pow()

Browse Source
This commit is contained in:
nemu
2010-03-08 14:36:28 +00:00
parent 842463dc23
commit fe55074160
1 changed files with 8 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
src/classes/PFunction.cpp
View File

@ -472,7 +472,14 @@ Double_t PFunction::EvalNode(PFuncTreeNode &node)
} }
} else if (node.fID == PFunctionGrammar::powerID) { } else if (node.fID == PFunctionGrammar::powerID) {
if (node.fFunctionTag == FUN_POW) { if (node.fFunctionTag == FUN_POW) {
return pow(EvalNode(node.children[0]), EvalNode(node.children[1])); Double_t base = EvalNode(node.children[0]);
Double_t expo = EvalNode(node.children[1]);
// check that no complex number will result
if (base < 0.0) { // base is negative which might be fatal
if (expo-floor(expo) != 0.0) // exponent is not an integer number, hence take -base (positive) to avoid complex numbers, i.e. nan
base = -base;
}
return pow(base, expo);
} else { } else {
cerr << endl << "**PANIC ERROR**: PFunction::EvalNode: node.fID == PFunctionGrammar::powerID: you never should have reached this point!"; cerr << endl << "**PANIC ERROR**: PFunction::EvalNode: node.fID == PFunctionGrammar::powerID: you never should have reached this point!";
cerr << endl; cerr << endl;