feature_map = feature_map.view(1, feature_map.shape[0], feature_map.shape[1], feature_map.shape[2])解释大妈
时间: 2023-09-14 19:03:15 浏览: 125
这段代码的作用是将一个三维的特征图(feature_map)转换为四维张量。
具体地,这个特征图的维度是[channels, height, width],其中channels表示特征图的通道数,height表示特征图的高度,width表示特征图的宽度。
view函数是PyTorch中的一个函数,用于改变张量的形状。这里使用view函数将特征图的维度从[channels, height, width]转换为[1, channels, height, width],其中1表示batch_size的大小,即将单张特征图转换为一个batch。这样做是为了方便在神经网络中进行处理。
需要注意的是,view函数只是改变张量的形状,不改变张量的内容。如果要改变内容,需要使用其他的函数,如reshape函数。
相关问题
import arcpy # 设置工具箱参数 input_features = arcpy.GetParameterAsText(0) # 输入要素图层 join_features = arcpy.GetParameterAsText(1) # 连接要素图层 output_features = arcpy.GetParameterAsText(2) # 输出要素图层 join_fields = arcpy.GetParameterAsText(3).split(';') # 连接要素图层中需要赋值的字段,用“;”隔开 area_threshold = arcpy.GetParameterAsText(4) # 面积阈值,只有面积大于该值的要素才会被连接 # 创建空间连接对象 spatial_join = arcpy.SpatialJoin_analysis(target_features=input_features, join_features=join_features, out_feature_class=output_features, join_operation="JOIN_ONE_TO_MANY", join_type="KEEP_ALL", match_option="INTERSECT") # 根据面积阈值进行筛选 if len(area_threshold) > 0: arcpy.SelectLayerByAttribute_management(in_layer_or_view=spatial_join, where_clause="Shape_Area >= {}".format(area_threshold)) # 设置字段映射 field_mapping = arcpy.FieldMappings() for field in join_fields: field_map = arcpy.FieldMap() field_map.addInputField(spatial_join, field) output_field = field_map.outputField output_field.name = "{}_{}".format(join_features, field) field_map.outputField = output_field field_mapping.addFieldMap(field_map) # 对要素进行赋值 arcpy.FeatureClassToFeatureClass_conversion(spatial_join, output_features, "", field_mapping)运行错误:IndentationError: unexpected indent (空间连接.py, line 17) 执行(空间连接多对一)失败。请改正代码
根据错误提示,第17行出现了意外的缩进。请检查该行以及前面的几行代码是否存在多余的空格或制表符。正确的代码应该是:
```python
# 创建空间连接对象
spatial_join = arcpy.SpatialJoin_analysis(target_features=input_features,
join_features=join_features,
out_feature_class=output_features,
join_operation="JOIN_ONE_TO_MANY",
join_type="KEEP_ALL",
match_option="INTERSECT")
# 根据面积阈值进行筛选
if len(area_threshold) > 0:
arcpy.SelectLayerByAttribute_management(in_layer_or_view=spatial_join,
where_clause="Shape_Area >= {}".format(area_threshold))
# 设置字段映射
field_mapping = arcpy.FieldMappings()
for field in join_fields:
field_map = arcpy.FieldMap()
field_map.addInputField(spatial_join, field)
output_field = field_map.outputField
output_field.name = "{}_{}".format(join_features, field)
field_map.outputField = output_field
field_mapping.addFieldMap(field_map)
# 对要素进行赋值
arcpy.FeatureClassToFeatureClass_conversion(spatial_join,
output_features,
"",
field_mapping)
```
import arcpy # 设置工具箱参数 input_features = arcpy.GetParameterAsText(0) # 输入要素图层 join_features = arcpy.GetParameterAsText(1) # 连接要素图层 output_features = arcpy.GetParameterAsText(2) # 输出要素图层 join_fields = arcpy.GetParameterAsText(3).split(';') # 连接要素图层中需要赋值的字段,用“;”隔开 area_threshold = arcpy.GetParameterAsText(4) # 面积阈值,只有面积大于该值的要素才会被连接 # 创建空间连接对象 spatial_join = arcpy.SpatialJoin_analysis(target_features=input_features, join_features=join_features, out_feature_class=output_features, join_operation="JOIN_ONE_TO_MANY", join_type="KEEP_ALL", match_option="INTERSECT") # 根据面积阈值进行筛选 if len(area_threshold) > 0: arcpy.SelectLayerByAttribute_management(in_layer_or_view=spatial_join, where_clause="Shape_Area >= {}".format(area_threshold)) # 检查 SelectLayerByAttribute_management 函数的输入参数是否正确 desc = arcpy.Describe(spatial_join) if desc.dataType == 'FeatureClass': # 设置字段映射 field_mapping = arcpy.FieldMappings() for field in join_fields: field_map = arcpy.FieldMap() field_map.addInputField(spatial_join, field) output_field = field_map.outputField output_field.name = "{}_{}".format(join_features, field) field_map.outputField = output_field field_mapping.addFieldMap(field_map) # 对要素进行赋值 arcpy.FeatureClassToFeatureClass_conversion(spatial_join, output_features, "", field_mapping) else: arcpy.AddError("SelectLayerByAttribute_management 函数的输入参数不是要素图层。")运行错误:IndentationError: unexpected indent (空间连接.py, line 12) 执行(空间连接多对一)失败。请改正代码
这个错误是缩进错误,可能是因为在第12行有额外的缩进。请检查代码中所有行的缩进是否正确,并调整缩进使其符合 Python 的语法规则。以下是已修正后的代码:
```
import arcpy
# 设置工具箱参数
input_features = arcpy.GetParameterAsText(0) # 输入要素图层
join_features = arcpy.GetParameterAsText(1) # 连接要素图层
output_features = arcpy.GetParameterAsText(2) # 输出要素图层
join_fields = arcpy.GetParameterAsText(3).split(';') # 连接要素图层中需要赋值的字段,用“;”隔开
area_threshold = arcpy.GetParameterAsText(4) # 面积阈值,只有面积大于该值的要素才会被连接
# 创建空间连接对象
spatial_join = arcpy.SpatialJoin_analysis(target_features=input_features, join_features=join_features, out_feature_class=output_features, join_operation="JOIN_ONE_TO_MANY", join_type="KEEP_ALL", match_option="INTERSECT")
# 根据面积阈值进行筛选
if len(area_threshold) > 0:
arcpy.SelectLayerByAttribute_management(in_layer_or_view=spatial_join, where_clause="Shape_Area >= {}".format(area_threshold))
# 检查 SelectLayerByAttribute_management 函数的输入参数是否正确
desc = arcpy.Describe(spatial_join)
if desc.dataType == 'FeatureClass':
# 设置字段映射
field_mapping = arcpy.FieldMappings()
for field in join_fields:
field_map = arcpy.FieldMap()
field_map.addInputField(spatial_join, field)
output_field = field_map.outputField
output_field.name = "{}_{}".format(join_features, field)
field_map.outputField = output_field
field_mapping.addFieldMap(field_map)
# 对要素进行赋值
arcpy.FeatureClassToFeatureClass_conversion(spatial_join, output_features, "", field_mapping)
else:
arcpy.AddError("SelectLayerByAttribute_management 函数的输入参数不是要素图层。")
```
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