Product: TIBCO Spotfire®
"Too many categories on the axes" error in map chart
When creating a Map Chart and enabling the Tiled Marker option, the user can get a "Too many categories on the axes" error even though it appears that there is a reasonable number of categories on each axis. For example, the Map Chart may only have 100 points on the x-axis between -75.7 and 76.3, but Spotfire looks at every possible integer between the smallest and largest values, which is 152. Using a 200px visualization (200/152) results in 1.32 pixels per tile, which will produce visible markers.
If however, the user has 100 points between -75,700 and 76,300, Spotfire still calculates tile size based on every possible integer in the range. Again, using a 200px visualization (200/152,000) results in 0.00132 pixels per tile which is too small to be visible. When using Tiled Markers, the user must keep in mind the total range on the x- and y-axes, not just the number of points in the data, and adjust the settings accordingly. Dividing x- and y-axis values by a common value, such as 1,000 in the given example, will display an accurate Map Chart without error.