Hi I would like to plot a graph of load voltage vs load current, I have been trying to do it with a `tikzpicture`

, but wonder if maybe it can be done with a `tikzplot`

? The bellow code is sort of what I am after, I want to plot the data and measure the gradient and get the `yintercept`

, I'm quite new at using `pgfplot`

so quite a step learning curve for me. My plot points would be

```
P1(0.750,7.50)
P2(0.409,8.192)
P3(0.281,8.437)
...
```

I can figure out the equation for the line and put this on as a label?

```
\documentclass{article}
\usepackage{tikz}
\begin{document}
\begin{tikzpicture}
\draw [ultra thick,-latex] (0,0)--(10,0) node [right, above]{$I_L$ Load Current};
\draw [ultra thick,-latex] (0,0)--(0,12) node [right]{$V_L$Load Voltage};
\coordinate (X2) at (4,0);
\coordinate (X1) at (6,0);
\coordinate (P1) at (0,5);
\coordinate (P2) at (0,7);
\coordinate (b) at (4,5);
\coordinate (d) at (6,7);
\coordinate (a) at (4,7);
\coordinate (c) at (6,5);
\node at (X2) [below] {$X2$};
\node at (X1) [below] {$X1$};
\node at (P2) [left] {$P2$};
\node at (P1) [left] {$P1$};
\draw [dashed] (a)node [above right] {$a$}--(X2);
\draw [dashed] (d)node [above right] {$d$}--(X1);
\draw [dashed] (P1)--(c)node [above right] {$c$};
\draw (P2)--(d)node [above right] {$d$};
\node at (b) [above right]{$b$};
%\draw (d)--++(0:2)node [right] {$ MC=AC$};
\draw (c)--(a)--++(135:5.65);
\draw (c)--++(-45:2) node [below] {$D$};
\end{tikzpicture}
\end{document}
```

This is what I have so far, but cant get it to look like the above example.. I'd like to take the dashed lines from some of my data points

```
\documentclass[convert = false, border=10pt]{standalone}
% http://sourceforge.net/projects/pgfplots/
\usepackage{pgfplots}
\usepackage{amsmath}
\usepackage{steinmetz}
\begin{document}
\begin{tikzpicture}
\begin{axis}[
xlabel=Voltage,
ylabel=Current]
\addplot[color=blue,mark=x] coordinates {
(0.750,7.5)
(0.409,8.192)
(0.2812,8.437)
(0.2143,8.571)
};
\end{axis}
\end{tikzpicture}
\end{document}
```

## Best Answer

This is one possible solution where the linear regression from

`pgfplotstable`

library is utilized. And the linear model is computed and shown in the legend.`Y interception`

is also shown in the graph.Code