"Too many categories on the axes" error in map chart

"Too many categories on the axes" error in map chart

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Article ID: KB0083632

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Updated On:

Products Versions
Spotfire Analyst 7.0, 7.5, 7.6, 7.7, 7.8, 7.9, 7.10

Description

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.

Environment

All supported environments

Resolution

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.

Issue/Introduction

When using the Tiled Markers option in a Map Chart, the error "Too many categories on the axes" can come up unexpectedly.