| Week of Jan. 15 |
| Today’s agenda: | ||
| Announcements & reminders | ||
| MFworks operations | ||
| Give out assignment#2 | ||
| Continue work on assignment#1 | ||
| Announcements & Reminders |
| Still working on the printers | |
| Assignment #1 is due next week at the beginning of the lab | |
| Assignment #2 will be due week of Feb.5 | |
| Lab Supervisor orientation meeting this Thursday afternoon (Jan. 18) |
| Does anyone need help formating a PC Zip disk for the Mac? |
| Important raster GIS concept |
| Data is numeric | |
| Operations work on the data not the map colours | |
| MFworks operations and functions |
| Cover | |
| Recode | |
| Slice | |
| Spread | |
| Clump | |
| Count function |
| Operation Taxonomy |
| Group 1: Basic operations on 1 Layer | ||
| Explicit renumbering (= Recode) | ||
| Automatic renumbering (=Slice) | ||
| Basic measurement (=Spread) | ||
| Adjacency assessment (=Clump) | ||
| Group 2: Basic operations on n layers | ||
| Layer superimposition (=Cover) | ||
| Cover operation |
| A Group2 operation: Layer Superimposition | ||
| The Cover operation is used for two main purpose: | ||
| 1) overlaying map layers | ||
| 2) for mosaicking map layers | ||
| Cover operation overlay statement format |
| Newmap = Cover maplayer1 | |
| with maplayer2 | |
| with maplayer3 ; |
| "Cover" |
| Cover |
| Cover operation mosaic statement format |
| Newmap = Cover maplayer1 | |
| with maplayer2 | |
| mosaic ; |
| Slide 11 |
| Recode operation |
| A Group 1 operation: Explicit Renumbering | |
| Generates a new map layer | |
| You specify the zones from the input map that will appear in the output map | |
| Use the “…” operator for specifying number ranges (from the keypad menu in the script window) |
| Recode statement format |
| newmap = Recode oldmap | |
| Assigning newvalue To existingvalue ; |
| Recode modifiers |
| newmap = Recode oldmap | |
| Assigning newval To existval Assigning newval2 To existval2…existval3 | |
| Assigning newval3 To existval4 … Assigning newval4 To … existval5 Assigning newval5 To … | |
| CarryOver ; | |
| Slice operation |
| A group 1 operation: Automatic Renumbering | |
| Slice may be thought of as an “automatic” recode |
| The concept of “Slice” |
| It divides the range of values in an input map into equal sized groups | |
| Each group becomes a zone in the output map |
| An example of the Slice in action Here is a map |
| The legend for this map looks like this |
| The same map after being sliced into 5 |
| The resulting legend has only 5 zones |
| Slice operation statement format |
| Newmap = Slice inputmap into value ; | ||
| modifiers of Slice |
| Newmap = Slice inputmap into value by value range value range use topvalue use middlevalue use bottomvalue makerangelabels ; | |
| Spread operation |
| A Group 1 operation: Basic Measurement | |
| Measures distances from specified cells | |
| Spread statement format |
| newmap = Spread oldmap | |
| To maximum distance ; | |
| Spread will measure the distances starting from any non-void cells in the input map. |
| Clump |
| A Group 1 operation: Adjacency Assessment | |
| “Clump” is used to group together or join together cells | |
| From the MFworks guide: “The Clump operation creates a map layer in which cells with the same value, within a specified distance of each other, are assigned a common unique value.” |
| Format of the Clump operation |
| NewMap = Clump inputmap at Distance ; |
| The Clump in action |
| Clumped at distance 1 |
| Clumped at distance 1.5 |
| Clumped at distance 3 |
| Another new item: The Count function |
| Value | |
| field |
| The Count in action |
| Binary Maps |
| A mask map is a special type of binary map |
| When to use masks |
| Masks are used to restrict GIS operations to a specific area | |
| Masks are used to ‘blot’ out areas or regions in a map | |
| Assignment #2 |
| Gain experience working with Basic Operations (I and II) as they are implemented in MFworks | ||
| Also develop | ||
| Scripting skills | ||
| Spatial processing | ||
| Cartographic layout and design | ||
| Problem solving | ||
| "2 part assignment" |
| 2 part assignment | ||
| Part 1 - work on Spatial Relations. Measuring distances and areas | ||
| Part 2 - concept of Competing Distances and cartographic visualization. | ||
| Advice |
| Work on this assignment on your own | ||
| You will get more out of it if you try to develop your problem solving skills | ||
| You will need the experience with writing scripts and the concepts of the operations when it comes to exam time | ||
| Read over the entire assignment before beginning it |
| Familiarize yourself with the structure of it | |
| Note the section at the back on output tips and try to apply them to your layouts |
| Things to remember from last week |
| Keep your files organized - make an Assignment#2-yourname folder for this assignment |
| That’s all |
| Use the time to finish up Assignment #1 and maybe start Assignment #2 | |||
| The lab should be open starting next week for drop in work sessions | |||