MATLAB Function Reference |

**Syntax**

**Description**

Error bars show the confidence level of data or the deviation along a curve.

```
errorbar(Y,E)
```

plots `Y`

and draws an error bar at each element of `Y`

. The error bar is a distance of `E(i)`

above and below the curve so that each bar is symmetric and `2*E(i)`

long.

```
errorbar(X,Y,E)
```

plots `X`

versus `Y`

with symmetric error bars `2*E(i)`

long. `X`

, `Y`

, `E`

must be the same size. When they are vectors, each error bar is a distance of `E(i)`

above and below the point defined by `(X(i),Y(i))`

. When they are matrices, each error bar is a distance of `E(i,j)`

above and below the point defined by `(X(i,j),Y(i,j))`

.

```
errorbar(X,Y,L,U)
```

plots `X`

versus `Y`

with error bars `L(i)+U(i)`

long specifying the lower and upper error bars. `X`

, `Y`

, `L`

, and `U`

must be the same size. When they are vectors, each error bar is a distance of `L(i)`

below and `U(i)`

above the point defined by `(X(i),Y(i))`

. When they are matrices, each error bar is a distance of `L(i,j)`

below and `U(i,j)`

above the point defined by `(X(i,j),Y(i,j))`

.

`errorbar(...,`

draws the error bars using the line type, marker symbol, and color specified by

)
*LineSpec*`LineSpec`

.

```
h = errorbar(...)
```

returns a vector of handles to line graphics objects.

**Remarks**

When the arguments are all matrices, `errorbar`

draws one line per matrix column. If `X`

and `Y`

are vectors, they specify one curve.

**Examples**

Draw symmetric error bars that are two standard deviation units in length.

**See Also**

Basic Plots and Graphs for related functions

error | errordlg |