## Beyond Matlab Plot Functionality, Example 1

The filter effects of SVG enhance the professional impression of a plot. But use them carefully in technical publications. There, the content is important! The rest is fine tuning. However, for eye-catching effects the filters are very powerful. The following example demonstrates the steps to turn a rather boring statistical plot into an eye-catcher. This method can be used to automatically generate plots from data sets. Thus, scripting can be used to automatically publish data.

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```function tutorial_plot2svg_beta % First, let's look at the temperature in Germany depending on the month % (averaged 1961-1990, source http://de.wikipedia.org/wiki/Klima) name={'Januar','Februar','March','April','May','June','July', ... 'August','September','Oktober','November','December'}; avgT =[-0.5 0.5 3.7 7.6 12.2 15.5 17.1 16.9 13.8 9.4 4.2 0.9]; minT =[-3.0 -2.5 0.0 3.0 7.3 10.6 12.3 12.0 9.3 5.7 1.6 -1.5]; maxT =[ 2.0 3.4 7.5 12.1 17.2 20.4 22.0 21.9 18.4 13.1 6.9 3.2]; % Draw a new figure and set the default values for the text font fig = figure; set(fig,'DefaultAxesFontName', 'Arial') set(fig,'DefaultAxesFontSize', 16) % Let's plot the data h = plot( 1:12, maxT, 1:12, avgT, 1:12, minT); % Now we change the XTickLabels set(gca, 'XTick', 1:12); set(gca, 'XTickLabel', name); % We change the LineWidth ... set(h(2), 'LineWidth', 12); set(h([1 3]), 'LineWidth', 8); set(gca, 'LineWidth', 2); % ... and add a legend [h1,h2] = legend(h, {'Max T', 'AvgT', 'Min T'}); % Next we add a title, ylabel, grid, box on title('Temperature in Germany (1961-1990)'); ylabel('T [°C]'); grid on box on axis([1 12 -5 25])```

``` % Up to here we have created a standard Matlab figure. % We create a svg plot as reference`````` plot2svg_beta('temperature_standard.svg');% Let's improve first the x-axis. The labels overlap. This doesn't look % nice. Unfortunately, the tickmark labels do not have the same Matlab % properties as standard text. Therfore, it is not possible to rotate them. setting.svg.XTickLabelAngle = -40;`````` set(gca, 'UserData', setting); % Just turning the labels won't help, as they would be cut at the bottom. % Therefore, we shift the axes position up. set(gca, 'Position', [0.13 0.21 0.720 0.715]); % Now let's beautify the plot by adding some light and shadow drop_shadow_lighting(h); drop_shadow_lighting(h2(2:end)); plot2svg_beta('temperature_nicer.svg'); % But, this is not enough. To make it perfect we replace the line color by % a background pixel image (1px x 50px). This pixel image is scaled to cover % the whole axes region. colors = reshape(flipud(jet(50)),[50 1 3]); imwrite(colors, 'gradient.png', 'png') % To add the pixel image the used filter chain is modified. drop_shadow_lighting_background(h, 'gradient.png'); drop_shadow_lighting_background(h2(2:end), 'gradient.png'); plot2svg_beta('temperature_perfect.svg'); % Filters are a very powerful feature of SVG. Unfortunately, not all SVG % render tools give full support. The best browser for SVG filters at the % moment seems to be Opera directly followed by Firefox. For Inkscape I had % to add a workaround in the plot2svg as it does not correctly handle % feImage filters. IE + RENESIS will not work as it does not support % filters. IE + Adobe may work, but is not tested. The Safari browser may % also fully support filters (not tested).```

``` function drop_shadow_lighting(s) % Draws a shadow and adds light effects. % PRELIMINARY IMPLEMENTATION (Parameters may change) % Parameters: % s : Array of plot object handles svgBoundingBox(s, 'axes', 12, 'off'); svgGaussianBlur(s, 'SourceAlpha', 2, 'blur'); svgSpecularLightingDistant(s, 'blur', 1, 16, 2, 225, 45, 'lighting') svgComposite(s, 'lighting', 'SourceGraphic', 'atop', 'obj'); svgGaussianBlur(s, 'SourceAlpha', 5, 'blur2'); svgOffset(s, 'blur2', [8 7], 'shade'); svgComposite(s, 'obj', 'shade', 'over', 'final');```

``` function drop_shadow_lighting_background(s, background) % Draws a shadow and adds light effects. The edge and face color of the % elements is replaced by a background pixel graphic that is scaled to % cover the axes % PRELIMINARY IMPLEMENTATION (Parameters may change) % Parameters: % s : Array of plot object handles svgBoundingBox(s, 'axes', 12, 'off'); svgGaussianBlur(s, 'SourceAlpha', 2, 'blur'); svgSpecularLightingDistant(s, 'blur', 1, 16, 2, 225, 45, 'lighting') svgImage(s, background, 'none', 'pic'); svgComposite(s, 'pic', 'SourceGraphic', 'atop', 'cut_pic'); svgComposite(s, 'lighting', 'cut_pic', 'atop', 'obj'); svgGaussianBlur(s, 'SourceAlpha', 5, 'blur2'); svgOffset(s, 'blur2', [8 7], 'shade'); svgComposite(s, 'obj', 'shade', 'over', 'final'); ```

### Plot Result of the Example

Pixelgraphics of the SVG Plot.

View the SVG plot