# ccylin

Central Cylindrical Projection

Cylindrical

`ccylin`

## Graticule

Meridians: Equally spaced straight parallel lines.

Parallels: Unequally spaced straight parallel lines, perpendicular to the meridians. Spacing increases toward the poles, more rapidly than that of the Mercator projection.

Poles: Cannot be shown.

Symmetry: About any meridian or the Equator.

## Features

This is a perspective projection from the center of the Earth onto a cylinder tangent at the Equator. It is not equal-area, equidistant, or conformal. Scale is true along the Equator and constant between two parallels equidistant from the Equator. Scale becomes infinite at the poles. There is no distortion along the Equator, but it increases rapidly away from the Equator.

## Parallels

For cylindrical projections, only one standard parallel is specified. The other standard parallel is the same latitude with the opposite sign. For this projection, the standard parallel is by definition fixed at 0º.

## Remarks

• The origin of this projection is unknown; it has little use beyond the educational aspects of its method of projection and as a comparison to the Mercator projection, which is not perspective. The transverse aspect of the central cylindrical is called the Wetch projection.

• This implementation of the central cylindrical projection is applicable only for coordinates that are referenced to a sphere.

## Limitations

Data at latitudes greater than 75º is trimmed to prevent large values from dominating the display.

## Example

```landareas = shaperead('landareas.shp','UseGeoCoords',true); axesm ('ccylin', 'Frame', 'on', 'Grid', 'on'); geoshow(landareas,'FaceColor',[1 1 .5],'EdgeColor',[.6 .6 .6]); tissot;```

## Version History

Introduced before R2006a