stem

Stem plot

Usage

stem(y)

• y should be a real scalar, vector or matrix (array having 2 dimensions).
• If y is a scalar, only the point [1, y] is plotted.
• If y is a vector (row or column) of length k, then k data points is plotted.
• If size(y) is a matrix of size [np,nl] with both np > 1 and nl > 1, then nl stem plots of np data points are plotted.
• It uses solid line with the default line colours and circle 'o' marker.
• If y has a value of NaN, Inf or -Inf, the value is ignored and no point is shown for that value.
• If y is real, it gives the same result as stem(1:np, y), where np is the number of rows of y.
• If y is complex, it gives the same result as stem(1:np, real(y)).

stem(y,spec)

• This is the same as stem(y) above, but it has additional controls over line attributes using the specification string spec.
• The specification string spec should be 'filled' or a character vector specifying values of various line attributes.
• When 'filled' is used, the line color will be used as the marker face color.
• 'filled' has no effect on markers for which color filling is impossible, for examples, cross 'x', dot '.', asterisk '*' and plus '+'.
• Not all line attributes are available for a spec. The available ones are 'color', 'lineStyle' and 'marker'.
• A line specification string is a concatenation of attribute values, e.g., '-r' means a solid line of red colour. An attribute value in a specification string can be over-written by a latter value in the same string. For example, '-.-' gives a solid line since '-.' (dash-dotted line) is overwritten by '-' (solid line). Similarly, 'blackred' gives a red line, instead of a black one.
• spec applies to all lines generated for y. Hence all lines have the same line and marker styles specified by spec.
• It gives the same result as stem(1:np, y, spec) where np is the number of rows of y.

stem(y,name1,value1,...,nameM,valueM)

stem(y,spec,name1,value1,...,nameM,valueM)

• name1, ..., nameM are attribute names, and value1, ..., valueM are their associated values.
• Attribute values specified by the specification string spec can be overwritten by value1, ..., valueM.

stem(x,y)

stem(x,y,spec)

stem(x,y,name1,value1,...,nameM,valueM)

stem(x,y,spec,name1,value1,...,nameM,valueM)

• x and y should be scalars, vectors, or matrices of numeric values.

• If y has size [m, n], where m >= 1 and n >= 1, then x should be either a matrix of the same size, or a vector of length m or n:

  • If x is a matrix, then n lines of m data points will be plotted.
  • If x is a vector of length m, then n lines of m data points will be plotted.
  • If x is a vector of length n, then m lines of n data points will be plotted.

• If x or y is complex, only the real parts will be used.

• See stem(y, 'spec') above for the description of the line specification string spec.

• name1, ..., nameM are attribute names, and value1, ..., valueM are their associated values.

Examples

• Stem plot of a sine function.

Input

x = linspace(-2*pi,2*pi);
stem(x,sin(x))

Output

• Calling stem(x,y) with y being a matrix, where np is the number of data points, and nl is the number of lines. Since x is a vector, all 3 stem plots have the same $x$-values.

Input

np = 20;
nl = 3;
y = rand(np,nl);
x = 1:np;
stem(x,y)
legend('show')
legend('Stem 1','Stem 2','Stem 3')
xlim([0.3 20.3])
ylim([-0.02 1.02])

Output

• Stem plot with filled red squares (rs and 'filled') and dashed-lines (--).

Input

y = rand(20,1);
x = 1:20;
stem(x,y,'--rs','filled')
xlim([0.3 20.3])
ylim([-0.02 1.02])

Output

• Stem plot with custom line and marker attributes.

Input

y = rand(20,1);
x = 1:20;
stem(x,y,'--rs','markersize',4,'markerfacecolor',[.4 .6 .7],'linewidth',3)
xlim([0.3 20.3])
ylim([-0.02 1.02])

Output