ArcMap 10.1 と 10.3 のスロープマップは異なります

Question

<\/HEAD>約1年前に ArcMap 10.1 で作成したスロープマップを調べていました。同じスロープマップを ArcMap 10.3 で計算すると、わずかに異なる結果が得られます。スロープの計算方法に何か変更がありましたか？1年前と同じ100m DEMを使用しています。また、10.1 のスロープマップは引き伸ばされた白黒のシンボロジーで開くのに対し、10.3 のスロープマップは分類されたシンボロジーで開くことに気付きました。以下のスクリーンショットは、最大スロープ値の増加を含むわずかな違いのある結果を示しています。<\/P><\/BODY><\/HTML>

DanPatterson_Retired · Answer

Ok perhaps next time we can leave out the coordinate system.

If... the raster has the exact same extent (check again) in rows and columns and in UTM coordinates AND it has the same cell size and there is a difference.

Is the difference just random? (a screen grab would really help)

Were you using slope in degrees for both OR slope in percent for both?

ThomasNupp · Answer

Here are the results of the raster calculations. As you can see by the range of values and the mean differences the two slope maps are different. 444, 6791100, 1001.15 MBGRIDGenericfloating point32 Bit-3.40282346639e+038absentabsentNoneBasicPermanent3953822.73375472874.114169517274.1141693885922.73375NAD_1983_UTM_Zone_15NMeter (1.000000)Degree (0.0174532925199433)5000000-930.99960D_North_American_1983skipped columns:1, rows:1, ignored value(s): -8.706651687622077.199062824249268-0.068358556105292541.0596882485126030

DanPatterson_Retired · Answer

It looks like the extent are the same and the cell size.

Now subtract them (either in the raster calculator or by using the Minus key).

You should have effectively 0 within floating point error.

Report back

(could just be a symbology thing... in which case, save the symbology from the old raster, and use it for the new raster in the import symbology from... portion of the symbology pane.)