From f4bde7d648c61e22fd4ed3170f00fc3eb5b3464b Mon Sep 17 00:00:00 2001
From: Peter Powers <pmpowers@usgs.gov>
Date: Wed, 3 Nov 2021 11:58:35 -0600
Subject: [PATCH 1/5] site string fix for logging
---
src/main/java/gov/usgs/earthquake/nshmp/DisaggCalc.java | 3 ++-
src/main/java/gov/usgs/earthquake/nshmp/HazardCalc.java | 2 +-
src/main/java/gov/usgs/earthquake/nshmp/RateCalc.java | 3 ++-
3 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/DisaggCalc.java b/src/main/java/gov/usgs/earthquake/nshmp/DisaggCalc.java
index 4c8224c72..3719b7301 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/DisaggCalc.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/DisaggCalc.java
@@ -23,6 +23,7 @@ import gov.usgs.earthquake.nshmp.calc.Hazard;
import gov.usgs.earthquake.nshmp.calc.HazardCalcs;
import gov.usgs.earthquake.nshmp.calc.HazardExport;
import gov.usgs.earthquake.nshmp.calc.Site;
+import gov.usgs.earthquake.nshmp.calc.Sites;
import gov.usgs.earthquake.nshmp.calc.ThreadCount;
import gov.usgs.earthquake.nshmp.internal.Logging;
import gov.usgs.earthquake.nshmp.model.HazardModel;
@@ -98,7 +99,7 @@ public class DisaggCalc {
log.info("");
List<Site> sites = HazardCalc.readSites(args[1], config, model.siteData(), log);
- log.info("Sites: " + sites);
+ log.info("Sites: " + Sites.toString(sites));
double returnPeriod = config.disagg.returnPeriod;
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/HazardCalc.java b/src/main/java/gov/usgs/earthquake/nshmp/HazardCalc.java
index 8218dc569..9773931f4 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/HazardCalc.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/HazardCalc.java
@@ -109,7 +109,7 @@ public class HazardCalc {
log.info("");
List<Site> sites = readSites(args[1], config, model.siteData(), log);
- log.info("Sites: " + sites);
+ log.info("Sites: " + Sites.toString(sites));
Path out = calc(model, config, sites, log);
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/RateCalc.java b/src/main/java/gov/usgs/earthquake/nshmp/RateCalc.java
index b923a90b8..8c59131d9 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/RateCalc.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/RateCalc.java
@@ -27,6 +27,7 @@ import gov.usgs.earthquake.nshmp.calc.CalcConfig;
import gov.usgs.earthquake.nshmp.calc.EqRate;
import gov.usgs.earthquake.nshmp.calc.EqRateExport;
import gov.usgs.earthquake.nshmp.calc.Site;
+import gov.usgs.earthquake.nshmp.calc.Sites;
import gov.usgs.earthquake.nshmp.calc.ThreadCount;
import gov.usgs.earthquake.nshmp.internal.Logging;
import gov.usgs.earthquake.nshmp.model.HazardModel;
@@ -107,7 +108,7 @@ public class RateCalc {
log.info("");
List<Site> sites = HazardCalc.readSites(args[1], config, model.siteData(), log);
- log.info("Sites: " + sites);
+ log.info("Sites: " + Sites.toString(sites));
Path out = calc(model, config, sites, log);
log.info(PROGRAM + ": finished");
--
GitLab
From 3e340cfdc47696f97610636c7358f91792b84e38 Mon Sep 17 00:00:00 2001
From: Peter Powers <pmpowers@usgs.gov>
Date: Wed, 10 Nov 2021 11:59:17 -0700
Subject: [PATCH 2/5] placeholder class for updates to hazard service
---
.../nshmp/www/services/HazardService2.java | 443 ++++++++++++++++++
1 file changed, 443 insertions(+)
create mode 100644 src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java b/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
new file mode 100644
index 000000000..f63e1f330
--- /dev/null
+++ b/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
@@ -0,0 +1,443 @@
+package gov.usgs.earthquake.nshmp.www.services;
+
+import static com.google.common.base.Preconditions.checkState;
+import static gov.usgs.earthquake.nshmp.calc.HazardExport.curvesBySource;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.EnumMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ExecutionException;
+import java.util.function.Function;
+
+import javax.inject.Singleton;
+
+import com.google.common.base.Stopwatch;
+
+import gov.usgs.earthquake.nshmp.calc.CalcConfig;
+import gov.usgs.earthquake.nshmp.calc.Hazard;
+import gov.usgs.earthquake.nshmp.calc.Site;
+import gov.usgs.earthquake.nshmp.data.MutableXySequence;
+import gov.usgs.earthquake.nshmp.data.XySequence;
+import gov.usgs.earthquake.nshmp.geo.Coordinates;
+import gov.usgs.earthquake.nshmp.geo.Location;
+import gov.usgs.earthquake.nshmp.gmm.Imt;
+import gov.usgs.earthquake.nshmp.model.HazardModel;
+import gov.usgs.earthquake.nshmp.model.SourceType;
+import gov.usgs.earthquake.nshmp.www.HazardController;
+import gov.usgs.earthquake.nshmp.www.Response;
+import gov.usgs.earthquake.nshmp.www.WsUtils;
+import gov.usgs.earthquake.nshmp.www.meta.DoubleParameter;
+import gov.usgs.earthquake.nshmp.www.meta.Metadata;
+import gov.usgs.earthquake.nshmp.www.meta.Parameter;
+import gov.usgs.earthquake.nshmp.www.meta.Status;
+import gov.usgs.earthquake.nshmp.www.services.ServicesUtil.ServiceQueryData;
+import gov.usgs.earthquake.nshmp.www.services.SourceServices.SourceModel;
+import io.micronaut.http.HttpRequest;
+import io.micronaut.http.HttpResponse;
+
+/**
+ * Probabilistic seismic hazard calculation handler for
+ * {@link HazardController}.
+ *
+ * @author U.S. Geological Survey
+ */
+@Singleton
+public final class HazardService2 {
+
+ private static final String NAME = "Hazard Service";
+
+ /** HazardController.doGetUsage() handler. */
+ public static HttpResponse<String> handleDoGetMetadata(HttpRequest<?> request) {
+ var url = request.getUri().getPath();
+ try {
+ var usage = new RequestMetadata(ServletUtil.model());// SourceServices.ResponseData();
+ var response = new Response(Status.USAGE, NAME, url, usage, url);
+ var svcResponse = ServletUtil.GSON.toJson(response);
+ return HttpResponse.ok(svcResponse);
+ } catch (Exception e) {
+ return ServicesUtil.handleError(e, NAME, url);
+ }
+ }
+
+ /** HazardController.doGetHazard() handler. */
+ public static HttpResponse<String> handleDoGetHazard(
+ HttpRequest<?> request,
+ RequestData args) {
+
+ try {
+ // TODO still need to validate
+ // if (query.isEmpty()) {
+ // return handleDoGetUsage(urlHelper);
+ // }
+ // query.checkParameters();
+
+ // var data = new RequestData(query);
+
+ Response<RequestData, ResponseData> response = process(request, args);
+ String svcResponse = ServletUtil.GSON.toJson(response);
+ return HttpResponse.ok(svcResponse);
+
+ } catch (Exception e) {
+ return ServicesUtil.handleError(e, NAME, request.getUri().getPath());
+ }
+ }
+
+ static Response<RequestData, ResponseData> process(
+ HttpRequest<?> request,
+ RequestData data) throws InterruptedException, ExecutionException {
+
+ var configFunction = new ConfigFunction();
+ var siteFunction = new SiteFunction(data);
+ var stopwatch = Stopwatch.createStarted();
+ var hazard = ServicesUtil.calcHazard(configFunction, siteFunction);
+
+ return new ResultBuilder()
+ .hazard(hazard)
+ .requestData(data)
+ .timer(stopwatch)
+ .url(request)
+ .build();
+ }
+
+ static class ConfigFunction implements Function<HazardModel, CalcConfig> {
+ @Override
+ public CalcConfig apply(HazardModel model) {
+ var configBuilder = CalcConfig.copyOf(model.config());
+ return configBuilder.build();
+ }
+ }
+
+ static class SiteFunction implements Function<CalcConfig, Site> {
+ final RequestData data;
+
+ private SiteFunction(RequestData data) {
+ this.data = data;
+ }
+
+ @Override // TODO this needs to pick up SiteData
+ public Site apply(CalcConfig config) {
+ return Site.builder()
+ .location(Location.create(data.longitude, data.latitude))
+ .vs30(data.vs30)
+ .build();
+ }
+ }
+
+ // public static class QueryParameters {
+ //
+ // final double longitude;
+ // final double latitude;
+ // final int vs30;
+ // final boolean truncate;
+ // final boolean maxdir;
+ //
+ // public QueryParameters(
+ // double longitude,
+ // double latitude,
+ // int vs30,
+ // boolean truncate,
+ // boolean maxdir) {
+ //
+ // this.longitude = longitude;
+ // this.latitude = latitude;
+ // this.vs30 = vs30;
+ // this.truncate = truncate;
+ // this.maxdir = maxdir;
+ // }
+ //
+ // // void checkParameters() {
+ // // checkParameter(longitude, "longitude");
+ // // checkParameter(latitude, "latitude");
+ // // checkParameter(vs30, "vs30");
+ // // }
+ // }
+
+ // private static void checkParameter(Object param, String id) {
+ // checkNotNull(param, "Missing parameter: %s", id);
+ // // TODO check range here
+ // }
+
+ /* Service request and model metadata */
+ static class RequestMetadata {
+
+ final SourceModel model;
+ final DoubleParameter longitude;
+ final DoubleParameter latitude;
+ final DoubleParameter vs30;
+
+ RequestMetadata(HazardModel model) {
+ this.model = new SourceModel(model);
+ // TODO need min max from model
+ longitude = new DoubleParameter(
+ "Longitude",
+ "°",
+ Coordinates.LON_RANGE.lowerEndpoint(),
+ Coordinates.LON_RANGE.upperEndpoint());
+
+ latitude = new DoubleParameter(
+ "Latitude",
+ "°",
+ Coordinates.LAT_RANGE.lowerEndpoint(),
+ Coordinates.LAT_RANGE.upperEndpoint());
+
+ vs30 = new DoubleParameter(
+ "Latitude",
+ "m/s",
+ 150,
+ 1500);
+ }
+ }
+
+ // static class RequestData {
+ //
+ // final double longitude;
+ // final double latitude;
+ // final double vs30;
+ // final boolean truncate;
+ // final boolean maxdir;
+ //
+ // RequestData(QueryParameters query) {
+ // this.longitude = query.longitude;
+ // this.latitude = query.latitude;
+ // this.vs30 = query.vs30;
+ // this.truncate = query.truncate;
+ // this.maxdir = query.maxdir;
+ // }
+ // }
+
+ private static final class ResponseMetadata {
+ final String xlabel = "Ground Motion (g)";
+ final String ylabel = "Annual Frequency of Exceedence";
+ final Object server;
+
+ ResponseMetadata(Object server) {
+ this.server = server;
+ }
+ }
+
+ private static String imtShortLabel(Imt imt) {
+ if (imt.equals(Imt.PGA) || imt.equals(Imt.PGV)) {
+ return imt.name();
+ } else if (imt.isSA()) {
+ return imt.period() + " s";
+ }
+ return imt.toString();
+ }
+
+ // @Deprecated
+ // static class RequestDataOld extends ServiceRequestData {
+ // final double vs30;
+ //
+ // RequestDataOld(Query query, double vs30) {
+ // super(query);
+ // this.vs30 = vs30;
+ // }
+ // }
+
+ private static final class ResponseData {
+ final ResponseMetadata metadata;
+ final List<HazardResponse> hazardCurves;
+
+ ResponseData(ResponseMetadata metadata, List<HazardResponse> hazardCurves) {
+ this.metadata = metadata;
+ this.hazardCurves = hazardCurves;
+ }
+ }
+
+ private static final class HazardResponse {
+ final Parameter imt;
+ final List<Curve> data;
+
+ HazardResponse(Imt imt, List<Curve> data) {
+ this.imt = new Parameter(imtShortLabel(imt), imt.name());
+ this.data = data;
+ }
+ }
+
+ private static final class Curve {
+ final String component;
+ final XySequence values;
+
+ Curve(String component, XySequence values) {
+ this.component = component;
+ this.values = values;
+ }
+ }
+
+ private static final String TOTAL_KEY = "Total";
+
+ private static final class ResultBuilder {
+
+ String url;
+ Stopwatch timer;
+ RequestData request;
+
+ Map<Imt, Map<SourceType, MutableXySequence>> componentMaps;
+ Map<Imt, MutableXySequence> totalMap;
+
+ ResultBuilder hazard(Hazard hazardResult) {
+ // TODO necessary??
+ checkState(totalMap == null, "Hazard has already been added to this builder");
+
+ componentMaps = new EnumMap<>(Imt.class);
+ totalMap = new EnumMap<>(Imt.class);
+
+ var typeTotalMaps = curvesBySource(hazardResult);
+
+ for (var imt : hazardResult.curves().keySet()) {
+
+ /* Total curve for IMT. */
+ XySequence.addToMap(imt, totalMap, hazardResult.curves().get(imt));
+
+ /* Source component curves for IMT. */
+ var typeTotalMap = typeTotalMaps.get(imt);
+ var componentMap = componentMaps.get(imt);
+
+ if (componentMap == null) {
+ componentMap = new EnumMap<>(SourceType.class);
+ componentMaps.put(imt, componentMap);
+ }
+
+ for (var type : typeTotalMap.keySet()) {
+ XySequence.addToMap(type, componentMap, typeTotalMap.get(type));
+ }
+ }
+
+ return this;
+ }
+
+ ResultBuilder url(HttpRequest<?> request) {
+ url = request.getUri().getPath();
+ return this;
+ }
+
+ ResultBuilder timer(Stopwatch timer) {
+ this.timer = timer;
+ return this;
+ }
+
+ ResultBuilder requestData(RequestData request) {
+ this.request = request;
+ return this;
+ }
+
+ Response<RequestData, ResponseData> build() {
+ var hazards = new ArrayList<HazardResponse>();
+
+ for (Imt imt : totalMap.keySet()) {
+ var curves = new ArrayList<Curve>();
+
+ // total curve
+ curves.add(new Curve(
+ TOTAL_KEY,
+ updateCurve(request, totalMap.get(imt), imt)));
+
+ // component curves
+ var typeMap = componentMaps.get(imt);
+ for (SourceType type : typeMap.keySet()) {
+ curves.add(new Curve(
+ type.toString(),
+ updateCurve(request, typeMap.get(type), imt)));
+ }
+
+ hazards.add(new HazardResponse(imt, List.copyOf(curves)));
+ }
+
+ Object server = Metadata.serverData(ServletUtil.THREAD_COUNT, timer);
+ var response = new ResponseData(new ResponseMetadata(server), List.copyOf(hazards));
+
+ return new Response<>(Status.SUCCESS, NAME, request, response, url);
+ }
+ }
+
+ private static final double TRUNCATION_LIMIT = 1e-4;
+
+ /* Convert to linear and possibly truncate and scale to max-direction. */
+ private static XySequence updateCurve(
+ RequestData request,
+ XySequence curve,
+ Imt imt) {
+
+ /*
+ * If entire curve is <1e-4, this method will return a curve consisting of
+ * just the first point in the supplied curve.
+ *
+ * TODO We probably want to move the TRUNCATION_LIMIT out to a config.
+ */
+
+ double[] yValues = curve.yValues().toArray();
+ int limit = request.truncate ? truncationLimit(yValues) : yValues.length;
+ yValues = Arrays.copyOf(yValues, limit);
+
+ double scale = request.maxdir ? MaxDirection.FACTORS.get(imt) : 1.0;
+ double[] xValues = curve.xValues()
+ .limit(yValues.length)
+ .map(Math::exp)
+ .map(x -> x * scale)
+ .toArray();
+
+ return XySequence.create(xValues, yValues);
+ }
+
+ private static int truncationLimit(double[] yValues) {
+ int limit = 1;
+ double y = yValues[0];
+ while (y > TRUNCATION_LIMIT && limit < yValues.length) {
+ y = yValues[limit++];
+ }
+ return limit;
+ }
+
+ @Deprecated
+ public static class Query extends ServiceQueryData {
+ Integer vs30;
+
+ public Query(Double longitude, Double latitude, Integer vs30) {
+ super(longitude, latitude);
+ this.vs30 = vs30;
+ }
+
+ @Override
+ public boolean isNull() {
+ return super.isNull() && vs30 == null;
+ }
+
+ @Override
+ public void checkValues() {
+ super.checkValues();
+ WsUtils.checkValue(ServicesUtil.Key.VS30, vs30);
+ }
+ }
+
+ public static final class RequestData {
+
+ final double longitude;
+ final double latitude;
+ final int vs30;
+ final boolean truncate;
+ final boolean maxdir;
+
+ public RequestData(
+ double longitude,
+ double latitude,
+ int vs30,
+ boolean truncate,
+ boolean maxdir) {
+
+ this.longitude = longitude;
+ this.latitude = latitude;
+ this.vs30 = vs30;
+ this.truncate = truncate;
+ this.maxdir = maxdir;
+ }
+
+ // void checkParameters() {
+ // checkParameter(longitude, "longitude");
+ // checkParameter(latitude, "latitude");
+ // checkParameter(vs30, "vs30");
+ // }
+ }
+
+}
--
GitLab
From 72a0380860441c6ce3737230e6ea363d99d3442c Mon Sep 17 00:00:00 2001
From: Peter Powers <pmpowers@usgs.gov>
Date: Wed, 10 Nov 2021 12:00:22 -0700
Subject: [PATCH 3/5] service call arg formatting
---
.../nshmp/www/HazardController.java | 25 +++++++++++++------
1 file changed, 18 insertions(+), 7 deletions(-)
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java b/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
index e85229e1c..af348a42f 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
@@ -4,8 +4,6 @@ import javax.inject.Inject;
import gov.usgs.earthquake.nshmp.www.services.HazardService;
import gov.usgs.earthquake.nshmp.www.services.HazardService.QueryParameters;
-
-import io.micronaut.core.annotation.Nullable;
import io.micronaut.http.HttpRequest;
import io.micronaut.http.HttpResponse;
import io.micronaut.http.annotation.Controller;
@@ -61,11 +59,24 @@ public class HazardController {
@Get(uri = "/{longitude}/{latitude}/{vs30}{?truncate,maxdir}")
public HttpResponse<String> doGetHazard(
HttpRequest<?> request,
- @Schema(minimum = "-360", maximum = "360") @PathVariable double longitude,
- @Schema(minimum = "-90", maximum = "90") @PathVariable double latitude,
- @Schema(minimum = "150", maximum = "3000") @PathVariable int vs30,
- @QueryValue(defaultValue = "false") @Nullable boolean truncate,
- @QueryValue(defaultValue = "false") @Nullable boolean maxdir) {
+
+ @Schema(minimum = "-360", maximum = "360")
+ @PathVariable
+ double longitude,
+
+ @Schema(minimum = "-90", maximum = "90")
+ @PathVariable
+ double latitude,
+
+ @Schema(minimum = "150", maximum = "3000")
+ @PathVariable
+ int vs30,
+
+ @QueryValue(defaultValue = "false")
+ boolean truncate,
+
+ @QueryValue(defaultValue = "false")
+ boolean maxdir) {
/*
* @Schema annotation parameter constraints only affect Swagger service
--
GitLab
From 666a5e3e2fa25f1007912d90e92a6e46d3da4fae Mon Sep 17 00:00:00 2001
From: Peter Powers <pmpowers@usgs.gov>
Date: Wed, 10 Nov 2021 14:57:26 -0700
Subject: [PATCH 4/5] increment lib
---
gradle.properties | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/gradle.properties b/gradle.properties
index c43d8bfaa..5c00229ce 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -8,7 +8,7 @@ junitVersion = 5.5.2
micronautVersion = 2.4.1
mnPluginVersion = 1.4.2
nodeVersion = 3.0.1
-nshmpLibVersion = 0.7.3
+nshmpLibVersion = 0.7.8
nshmpWsUtilsVersion = 0.1.2
shadowVersion = 5.2.0
spotbugsVersion = 4.2.4
--
GitLab
From 5f4a6cec784341571e768522eb0e6f6c5aec0187 Mon Sep 17 00:00:00 2001
From: Peter Powers <pmpowers@usgs.gov>
Date: Wed, 10 Nov 2021 15:01:32 -0700
Subject: [PATCH 5/5] spotless edits
---
.../nshmp/www/HazardController.java | 19 ++++++-------------
.../nshmp/www/services/HazardService2.java | 1 +
2 files changed, 7 insertions(+), 13 deletions(-)
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java b/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
index af348a42f..a655b9fa4 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/www/HazardController.java
@@ -4,6 +4,7 @@ import javax.inject.Inject;
import gov.usgs.earthquake.nshmp.www.services.HazardService;
import gov.usgs.earthquake.nshmp.www.services.HazardService.QueryParameters;
+
import io.micronaut.http.HttpRequest;
import io.micronaut.http.HttpResponse;
import io.micronaut.http.annotation.Controller;
@@ -60,23 +61,15 @@ public class HazardController {
public HttpResponse<String> doGetHazard(
HttpRequest<?> request,
- @Schema(minimum = "-360", maximum = "360")
- @PathVariable
- double longitude,
+ @Schema(minimum = "-360", maximum = "360") @PathVariable double longitude,
- @Schema(minimum = "-90", maximum = "90")
- @PathVariable
- double latitude,
+ @Schema(minimum = "-90", maximum = "90") @PathVariable double latitude,
- @Schema(minimum = "150", maximum = "3000")
- @PathVariable
- int vs30,
+ @Schema(minimum = "150", maximum = "3000") @PathVariable int vs30,
- @QueryValue(defaultValue = "false")
- boolean truncate,
+ @QueryValue(defaultValue = "false") boolean truncate,
- @QueryValue(defaultValue = "false")
- boolean maxdir) {
+ @QueryValue(defaultValue = "false") boolean maxdir) {
/*
* @Schema annotation parameter constraints only affect Swagger service
diff --git a/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java b/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
index f63e1f330..ca235f7f9 100644
--- a/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
+++ b/src/main/java/gov/usgs/earthquake/nshmp/www/services/HazardService2.java
@@ -34,6 +34,7 @@ import gov.usgs.earthquake.nshmp.www.meta.Parameter;
import gov.usgs.earthquake.nshmp.www.meta.Status;
import gov.usgs.earthquake.nshmp.www.services.ServicesUtil.ServiceQueryData;
import gov.usgs.earthquake.nshmp.www.services.SourceServices.SourceModel;
+
import io.micronaut.http.HttpRequest;
import io.micronaut.http.HttpResponse;
--
GitLab