Hi,
I found that the TF3 class constructor
TF3::TF3(const char* name, const char* formula, Double_t xmin = 0,
Double_t xmax = 1, Double_t ymin = 0, Double_t ymax = 1, Double_t zmin =
0, Double_t zmax = 1)
doesn't work in root-3.05.07:
<root-session>
root [0] f3 = new TF3("f3", "x + y + z")
Error in <TF1::TF1>: function: f3/x + y + z has 3 parameters instead of 1
(class TF3*)0x88f7a18
root [1] f3_2 = new TF3("f3_2", "x + y")
Error in <TF1::TF1>: function: f3_2/x + y has 2 parameters instead of 1
Error in <TF3::TF3>: function: f3_2/x + y has 2 parameters instead of 3
(class TF3*)0x88fc040root [2] f3_1 = new TF3("f3_1", "x")
Error in <TF3::TF3>: function: f3_1/x has 1 parameters instead of 3
(class TF3*)0x88ee978root [3] f3_0 = new TF3("f3_0", "1")
Error in <TF3::TF3>: function: f3_0/1 has 1 parameters instead of 3
(class TF3*)0x88fc6a0
</root-session>
There is a note in the file
http://root.cern.ch/root/html/examples/V3.05.txt.html
possible related to the problem
2003-07-08 08:56 brun
* hist/src/: TF1.cxx, TF2.cxx, TF3.cxx:
Add protections in the constructors with a formula in case the dimension
of the formula does not match the class. The object is declared Zombie.
I think TF1 design conflicts with the TF1 <- TF2 <- TF3 inheritance
sequence. TF1 depends on relation between xmin and xmax:
<file name="hist/src/TF1.cxx">
// ...
// line 156
TF1::TF1(const char *name,const char *formula, Double_t xmin, Double_t xmax)
:TFormula(name,formula), TAttLine(), TAttFill(), TAttMarker()
// ...
// line 171
if (xmin < xmax ) {
fXmin = xmin;
fXmax = xmax;
} else {
fXmin = xmax; //when called from TF2,TF3
fXmax = xmin;
}
// ...
</file>
First xmin <-> xmax exchange:
<file name="hist/src/TF2.cxx">
// ...
// line 52
TF2::TF2(const char *name,const char *formula, Double_t xmin, Double_t
xmax, Double_t ymin, Double_t ymax)
:TF1(name,formula,xmax,xmin)
// ...
</file>
Second swap xmin and xmax:
<file name="hist/src/TF3.cxx">
// ...
// line 38
TF3::TF3(const char *name,const char *formula, Double_t xmin, Double_t
xmax, Double_t ymin, Double_t ymax, Double_t zmin, Double_t zmax)
:TF2(name,formula,xmax,xmin,ymin,ymax)
// ...
</file>
Now xmin < xmax again. The TF1 constructor emits a warning message
because it arguments look like in 1D case.
Maksim Nikulin
This archive was generated by hypermail 2b29 : Thu Jan 01 2004 - 17:50:14 MET