Cfrgtkky

Variations on this question have been asked multiple times before, but I have been unsuccessful in getting them to work. I may be (and most likely am) just inept at statistics.

I wish to plot a normal curve on top of this histogram using the data contained in the CSV file.

Many answers I have seen create a normal/gauss function, but I have excluded this from the MWE in case there is another, simpler way to do it.

Any assistance would be appreciated!

MWE:

begin{filecontents*}{data.csv}

A

2

3

4

2

3

4

5

6

9

9

1

end{filecontents*}



documentclass{standalone}

usepackage{pgfplots}

usepackage{filecontents}

usepackage{pgfplotstable}



begin{document}



begin{tikzpicture}

  centering

begin{axis}[

ybar interval,

/pgf/number format/.cd,

use comma,

1000 sep={},

title={Title},

xlabel={X Label},

ylabel={Y Label},

x label style={at={(axis description cs:0.5,-0.1)},anchor=north},

y label style={at={(axis description cs:0.05,0.5)},anchor=south},

xticklabel style={rotate=90, anchor=near xticklabel},

ytick distance=2,

width=textwidth, %10.5cm

height=6cm,

ymin=0

]



%%%

addplot +[

black,

fill=lightgray,

hist={bins=5,

data min=0,

data max=10,

}

] table[y=A, col sep=comma] {data.csv};



end{axis}

end{tikzpicture}

end{document}

Here is a proposal building on this answer.

documentclass{standalone}

usepackage{pgfplots}

usepackage{filecontents}

begin{filecontents*}{data.csv}

A

2

3

4

2

3

4

5

6

9

9

1

end{filecontents*}



usepackage{pgfplotstable}



newcommandGetMean[2]{% from https://tex.stackexchange.com/a/268942/121799

  pgfplotstableread{#1}tableA

  pgfplotstableset{

    create on use/new/.style={

    create col/expr={pgfmathaccuma + thisrow{#2}}},

  }

  pgfplotstablegetrowsof{tableA}

  pgfmathsetmacro{NumRows}{pgfplotsretval}

  pgfplotstablegetelem{numexprNumRows-1relax}{new}of{#1} 

  pgfmathsetmacro{Sum}{pgfplotsretval}

  pgfmathsetmacro{Mean}{Sum/NumRows}

}

newcommandGetVariance[3]{

  pgfplotstableread{#1}tableA

  pgfplotstableset{

    create on use/new/.style={

    create col/expr={pgfmathaccuma + (thisrow{#2}-#3)^2}},

  }

  pgfplotstablegetrowsof{tableA}

  pgfmathsetmacro{NumRows}{pgfplotsretval}

  pgfplotstablegetelem{numexprNumRows-1relax}{new}of{#1} 

  pgfmathsetmacro{SumSquares}{pgfplotsretval}

  pgfmathsetmacro{Variance}{sqrt(SumSquares)/NumRows}

}





begin{document}







begin{tikzpicture}[declare function={%

gauss(x,y,z)=1/(2*z*sqrt(pi))*exp(-(x-y)^2/(2*z^2));}]

begin{axis}[

/pgf/number format/.cd,

use comma,

1000 sep={},

title={Title},

xlabel={X Label},

ylabel={Y Label},

x label style={at={(axis description cs:0.5,-0.1)},anchor=north},

y label style={at={(axis description cs:0.05,0.5)},anchor=south},

xticklabel style={rotate=90, anchor=near xticklabel},

ytick distance=2,

width=textwidth, %10.5cm

height=6cm,

ymin=0

]



%%%

addplot +[ybar interval,

black,

fill=lightgray,

hist={bins=5,

data min=0,

data max=10,

}

] table[y=A, col sep=comma] {data.csv};

GetMean{data.csv}{A}



GetVariance{data.csv}{A}{Mean}



addplot[no marks,domain=0:8,smooth,samples=51,thick,color=blue]{Sum*gauss(x,Mean,Variance)};

end{axis}

end{tikzpicture}

end{document}