v0.7.3

v0.7.3 enhances the previous release with time-dependent accessibility evaluation, potential issue resolution on inconsecutive zone id's, and bug fix regarding connectors in DTALite.

Time-dependent Accessibility Evaluation

1. Evaluate any periodic accessibility using its corresponding VDF_fftt in link.csv;
2. Obtain periodic accessible nodes and links using using its corresponding VDF_fftt in link.csv;
3. Output shortest path distance info in addition path travel time (i.e., accessibility) in accessibility.csv;
4. Include zone coordinates in accessibility.csv and accessibility_aggregated.csv.

Potential Issue Resolution on Inconsecutive Zone ID's

As zone_id's are not necessarily consecutive numbers starting from zero, the previous implementation using list (with assumed consecutive zone id as index) would not go through if the assumption is violated.

Bug Fix on Connectors in DTALite

For an outgoing connector, its zone_seq_no_for_outgoing_connector should be the corresponding zone seq no of zone_org_id associated with the from node. See commit 5c65ff in DTALite for details.

Other Changes

1. Replace hard-coded 0.001, 0.0001 and similar with a constant SMALL_DIVISOR;
2. Replace the initial value of least_gradient_cost with MAX_LABEL_COST;
3. Change MAX_LABEL_COST to 999999;
4. Update path_engine so that MAX_LABEL_COST can be passed as a parameter to it at run-time.