[weigl]

I have used the following equations:

    set Re [expr {($velocity*$density*$bll)/$viscosity}]
    set cf [expr {pow((2*log10($Re))-0.65),(-2.3)}]
    set twall [expr {($cf/2)*$density*pow($velocity,2)}]
    set ustar [expr {sqrt($twall/$density)}]
    set deltas [expr {($yp*$viscosity)/($density*ustar)}]

but i keep getting this error

unexpected "," outside function argument list
in expression "pow((2*log10($Re))-0.65),(-2.3)"
    (parsing expression "pow((2*log10($Re))-0.6...")
    invoked from within
"expr {pow((2*log10($Re))-0.65),(-2.3)}"
    (procedure "afMesh" line 128)
    invoked from within
"afMesh"
    invoked from within
".mesh.af2.dbb invoke "
    invoked from within
".mesh.af2.dbb instate {pressed !disabled} { .mesh.af2.dbb state !pressed; .mesh.af2.dbb invoke } "
    (command bound to event)

what am I doing wrong here?

[tcarrigan]

You're missing a set of parentheses.

Your code: [expr {pow((2*log10($Re))-0.65),(-2.3)}]
Correct code: [expr {pow(((2*log10($Re))-0.65),(-2.3))}]