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Questions tagged [null]

NULL is a value for an attribute value that contains no data. Sometimes not allowed due to 'not null constraints' or slt.

2
votes
2answers
42 views

Selecting all values with <Null> by using SelectLayerByAttribute_management with input Parameter

I am trying to select all values with Null by using the SelectLayerByAttribute_management. But the Fieldname in the where-clause is alterable by using the input-parameter. That is what i tried: if ...
1
vote
3answers
31 views

Deleting blank fields in multiple shapefiles in folder using ArcPy?

I have some shapefiles and each shapefile is having some blank or zero value fields. My task is to delete blank/zero value fields for all shapefiles in the folder. I have searched for solution in ...
3
votes
2answers
105 views

How to Refer to a Null value with ArcPy Expressions

I feel like this might be a bit of a simple answer but I can't figure out how to refer to Null values in a field using an expression in python. I've tried using the following as well as = None and =...
2
votes
1answer
85 views

Blank values in attribute table don't work as null in QGIS?

I am using QGIS 3.4. I have a layer generated from the QuickOSM plugin with various pieces of OSM data. For lines 17-19 which do not have a value in the "name" attribute, I don't know why null ...
2
votes
2answers
124 views

Converting none to zero (0) in geodatabase table using ArcPy?

I have an attribute table looks like this How do I convert Nulls into 0? I've tried to set this table non nullable type but got this: while the official doc says this: At least one of them is ...
1
vote
3answers
71 views

Searching for NULL values in feature class table

I am looking for a way which I can search whole my feature class in ArcMap to find if has any NULL values on it. I know how can I do this with "Select By Attribute", but I am looking for a faster way ...
0
votes
2answers
33 views

Using cursor to delete rows with <Null> values in table using ArcPy?

I am trying to delete any record in my table that has a null value in a certain field (the Grid_Code field) and the code I have does not return any errors and seems to run fine, but doesn't actually ...
4
votes
1answer
115 views

Hiding NULL text in attributes using QGIS?

In QGIS 3, how do I hide the 'NULL' text from empty attributes? QGIS 2.18 has a setting for that, but can't find it in QGIS 3.4.
1
vote
0answers
25 views

Using Null Values in Raster To NumPy?

I am trying a convert a raster dataset [a simple 4 x 4] into a numpy array using RasterToNumPyArray. Here is my sample raster dataset: RasterToNumPyArray however, returns zero for Null values: ...
1
vote
2answers
47 views

Programmatically defining schema not working for nulls

I am attempting to create a table with appropriate schema. I have created a data dictionary with the appropriate values stored in a list. See below schema_dict = {"borough" : ["borough","TEXT","","",...
3
votes
2answers
77 views

Labeling vertical lines with Shape Length = 0 in ArcMap?

I am trying to add labels to my linear feature class. Some of my lines are vertical (i.e. I only see a point representing the start or end node of the line, because they have the same XY coordinates ...
2
votes
1answer
103 views

Condition if column from table is empty is not working?

I want to make a loop where if a column is empty in a row to do something else. The problem is that it can't determine the empty row. I tried as null, na , '',' ' and with double quotes and nothing. ...
1
vote
1answer
37 views

Why is there a NULL-entry in the “Fields and Values” section of the QGIS field calculator

In the QGIS field calculator you can choose the Fields you want to add to your field calculator expression. I wonder why there is also "NULL" listed as one option? Choosing NULL as a value makes ...
1
vote
1answer
38 views

Removing <Null> From all Fields and all Feature Classes in a GDB

Have a gdb with 13 FCs and 70 Fields in each FC (same fields). Some fields have 'Null with <> around', which I would like to remove. (Not the field itself or data point. As in set null to empty "") ...
0
votes
1answer
51 views

Changing -9999 into <null> using ArcGIS Desktop?

I am using ArcGIS Desktop 10.5. I have a shapefile with many -9999 values in multiple columns. Since I have to do mathematical calculations with the values (stuff like the numbers in row a are XY% ...
3
votes
1answer
317 views

QGIS: Delete all records/rows with NULL values

I have joined a CSV file to a shapefile by a common key in QGIS. Not all records in the shapefile and CSV had corresponding keys. This left some records in the shapefile as NULL. i.e. City ...
0
votes
1answer
47 views

ArcMap label expression returning NoneType error

I'm trying to create street range labels rounded to the nearest 100 unless a street range is less than 100 I'm using "50". I have a field l_refaddr that is a string with number ranges for a street ...
0
votes
0answers
13 views

Data type error in UpdateCursor [duplicate]

My issue is that I am getting an error statement that states the following: row[0] = row[2] / row[1] * 100 TypeError: unsupported operand type(s) for /: 'NoneType' and 'float' Here is the ...
0
votes
1answer
87 views

Meaning of NULL when using condition in gdal_calc

I am confused with the results of using a condition in gdal_calc. Initially I thought that gdal_calc was setting pixels to nodata where a condition is not met. In the documentation (http://www.gdal....
1
vote
2answers
209 views

Replace null pixels from one raster with values from another raster in QGIS

I have 2 rasters of the same area, one has some null pixels and the other one doesn't and I would like to fill in the nulls in raster 1 by values from raster 2. How to perform in raster calculator?
1
vote
1answer
55 views

Replace NULLs within a ListFields loop

I have some difficulties to change "NULL" values to zero in all "DOUBLE" fields in feature class. I have tried to make a script tool with the following Python code in ArcGIS 10.5 but it didn't work. ...
2
votes
1answer
183 views

Use gdal to set multiband raster values to no data

I need to set a 3 band multiband raster (GeoTIff) where band 1 = 0 AND band 2 = 0 AND band 3 = 0 then this is no data (0,0,0 is No Data). Not OR in each band but AND across the 3 bands. I think it is ...
0
votes
0answers
61 views

ENVI seamless mosaic incorrectly altering data?

I'm using ENVI 5.2 build 9/28/2014. I'm using AVIRIS data and calculated a vegetation index for six adjacent flight lines. For each individual flight line I know I calculated the index correctly, ...
1
vote
1answer
41 views

Can't assign a numeric value to a field that is set to <Null>

Within a feature class there's a number of records with a specific field (type double) set to . I've set up a cursor to assign those value a numeric number. However, I am getting an error. This is ...
0
votes
1answer
61 views

Null values being interpolates as 0 in QGIS

I have a file with data fields which I have imported as CSV. When I look at the Field Attribute Table, the empty fields appear clearly as NULL values. However when I interpolate the data, the NULL ...
1
vote
1answer
165 views

Understanding raster custom transparency options (making null data 100% transparent) in QGIS?

I have a raster with a large null area (see the solid black area in the image below). The "Band 1" value throughout this null area is -3.402823e+38. I'm trying to make sense of the result of my ...
2
votes
1answer
274 views

Batch removing null geometries

Is there a way batch remove or delete null geometries from hundreds of small polygon vector files in QGIS, while saving the new clean file to their original directories? I can't check for and fix ...
0
votes
1answer
50 views

Expression Area Statistic Results in NULL with Real Number Conversion

I am attempting to determine the ratio of a statistic to the area of corresponding geometry while accounting for outliers through a standard deviation filter. While the QGIS Expression Editor ...
3
votes
1answer
114 views

FME shapefile writer NULL values in date format fields

I have a data source with string fields containing dates formatted like 20180202120000 (YYYYMMDDhhmmss) and I would like to write these in date fields in a shapefile using FME (2016.1). UPDATE: ...
2
votes
1answer
51 views

QGIS - formula works in the attribute table fine but getting error when using the model builder

So I am using QGIS 2.18.15 Strange thing: If I go via the attribute table into the field calculator and use following formula it works just fine: if( "DB_arit" IS NULL, 0, "DB_arit" ) ...
0
votes
0answers
28 views

Exporting from REST endpoint returns null values for shape length

I have a script that queries a REST endpoint, exports the data in JSON, and converts it to a feature class. Mostly works pretty well. However, the Shape_length field has all Null values. What's even ...
1
vote
1answer
133 views

Representing NULL data for a numeric field in ArcGIS (symbology)

I have a tank age data set which I would like to present on ArcGIS. I would like to represent the different tanks using their tank age. I would like the symbol colour to be dependent on the tank age (...
1
vote
0answers
44 views

QGis server : 0 is wrote instead of “null”

I am trying to load PostGis data on QGis (client) with QGis server (WFS). Unfortunately, missing values and NULL values for numbers appear as 0. Here is what I tried: specified variable ...
0
votes
1answer
33 views

Runtime error arcpyy using fields[f].append(row.getValue(f))

I am trying to write a arcpy script that will turn off all NULL and empty fields. The script runs for a while and then gives a run time error at fields[f].append(row.getValue(f)). Below is the ...
-2
votes
1answer
266 views

Search Cursor to count not null values records?

I am trying to achieve print all featureclass, total count, notNullvalues. I am trying hard on this code. but getting Error: suggest how can I code better and working. I am not regular python user. ...
1
vote
1answer
166 views

Creating null values when creating raster in arcgis

I am converting a large set of polygons into a single raster where all of the polygon values are 1. When I do this I do not have null values (0) for the rest of the cells. I looked through polygon to ...
2
votes
0answers
84 views

NULL values in QGIS attribute tables not appearing

'NULL' is not appearing in my QGIS attribute tables. Columns that used to have 'NULL' in them are now just empty. What could be the problem?
2
votes
2answers
126 views

Does ArcMap have search and replace function over several fields at once for NULL values?

I am trying to replace all "Null" values to "0", over all fields. I am quite sure this is wishfull thinking, but it's worth asking ! Is there a tool which performs this ? (as well as the opposite ...
1
vote
1answer
55 views

Removing Null Values and Slicing Results

I am attempting to label features that can have multiple combinations of codes. The label is based off of three fields ([DescriptionA], [DescriptionB], [DescriptionC]). I'd like to create a python ...
-1
votes
1answer
152 views

Counting non-null attributes using ArcGIS Field Calculator?

I have an ESRI featureclass with a lot of records that have been scored to certain criteria, although criteria have been left null for records where they aren't deemed relevant. I'm now trying to ...
1
vote
1answer
603 views

ArcGIS API for JavaScript won't add graphics to map

var point = new Point(-49.9, 39.3) var symbol = new PictureMarkerSymbol('http://www.prww-weather.com/hurricane/icons/post-tropical-cyclone.png', 50, 50) var graphic = new Graphic(point, symbol); map....
0
votes
2answers
193 views

Why is my field not nullable when no value is NULL?

I am quite new to arcpy. My script seemed to work just fine but I get an error, "the field is not nullable". I guess the problem is with the last block of code but I don't understand why nor how to ...
5
votes
2answers
241 views

Can a SHAPE field be non-nullable?

I'm using ArcMap 10.2, I'd like to restrict the type of records that makes their way into a feature class to only those with a geometry. Is there a way to create feature class in a geodatabase where ...
6
votes
1answer
465 views

Working with NaN/null and different extents in QGIS Raster calculator?

When it comes to NULL value and different extents of rasters I find it extremely cumbersome to use QGIS raster calculator. As far as I am aware there is no way to operate with NaN/Null value. So no ...
1
vote
1answer
130 views

QGIS coloring NULL values

I am using QGIS Version 2.14.3. I have a map with polygons and a lot of different attributes. Some polygons have NULL values in some columns. I've tried to color the polygons with properties->style->...
0
votes
0answers
165 views

Zonal statistics results in some NULL values in QGIS?

I used zonal statistics through QGIS to assign raster image values to polygons. Here, Raster image has value in range from 0 to 238.567. As a result, some NULL values are assigned to polygons, even ...
0
votes
1answer
369 views

Why ExtractMultiValuesToPoints not working for Point file?

I'm struggling to extract depths from a bathymetry raster to a Point file with multiple features (not Multipoint, as I previously mis-stated). In trying to use ExtractMultiValuesToPoints(), I noticed ...
0
votes
1answer
965 views

Selecting blank values within a table

I am selecting the following to remove NULL values from a selection, but unable to remove BLANK values from the selection. Would selecting BLANK values only be done by using a string length of 0? I ...
1
vote
1answer
66 views

PostGIS to GeoJSON returning inordinate number blank records

I'm using the below code to generate GeoJSON from a Postgres95 table. When parsing out samples eg a months worth of crime data, which should be ~20k records for the month of March 2016, I'm getting a ...
2
votes
1answer
88 views

Replacing NULL values, loop skips records using Python, OGR, Rtree?

I have a point layer with several NULL values and based on a near analysis with another layer, I would like to replace those NULLs. However, with the code I use it only does a couple and then stops. ...