Google Earth Engine——Layer error: Description length exceeds maximum.解决办法

问题：

图片上的问题主要在于imag5.sum().clip(table),

另外，如果是imagecollection的话不能直接裁剪，不许经过一系列运算，也就是镶嵌mosaic()或者.first()编程一张影像才可以进行裁剪和reduceRegion()等一些列最大值、最小值、平均值的计算

Map.addLayer(eeObject, visParams, name, shown, opacity)

Adds a given EE object to the map as a layer.

Returns the new map layer.

Arguments:

eeObject (Collection|Feature|Image|RawMapId):

The object to add to the map.

visParams (FeatureVisualizationParameters|ImageVisualizationParameters, optional):

The visualization parameters. For Images and ImageCollection, see ee.data.getMapId for valid parameters. For Features and FeatureCollections, the only supported key is "color", as a CSS 3.0 color string or a hex string in "RRGGBB" format. Ignored when eeObject is a map ID.

name (String, optional):

The name of the layer. Defaults to "Layer N".

shown (Boolean, optional):

A flag indicating whether the layer should be on by default.

一个标志，表示该层是否应该默认打开。

opacity (Number, optional):

The layer's opacity represented as a number between 0 and 1. Defaults to 1.

图层的不透明度，用0到1之间的数字表示，默认为1。

Returns: ui.Map.Layer

这里一般只选择用前三个参数就够用了！

Map.addLayer(result_ndvi, visParam, 'Matched study area ndvi image method2');

result_ndvi,争取将所有的参数都在外面计算完成，完了直接放变量在这个里面，避免计算超限等等不必要的错误。